Actual source code: openglops.c
petsc-3.10.5 2019-03-28
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      2: /*
      3:     Defines the operations for the OpenGL PetscDraw implementation.

      5:     The eventual plan is to have a window system independent portion (that only uses gl...() routines) plus
      6:       several implementations for different Window interfaces:
      7:        --  glut (implmented)
      8:        --  Apple IOS  EAGLContext  https://developer.apple.com/library/ios/#documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/WorkingwithOpenGLESContexts/WorkingwithOpenGLESContexts.html#//apple_ref/doc/uid/TP40008793-CH2-SW1
      9:        --  Apple  NSOpenGLView  http://developer.apple.com/library/mac/#documentation/graphicsimaging/conceptual/OpenGL-MacProgGuide/opengl_pg_concepts/opengl_pg_concepts.html#//apple_ref/doc/uid/TP40001987-CH208-SW1
     10:        --  Apple  CGLContextObj http://developer.apple.com/library/mac/#documentation/graphicsimaging/Reference/CGL_OpenGL/Reference/reference.html#//apple_ref/doc/uid/TP40001186
     11: */

     13:  #include <petsc/private/drawimpl.h>
     14: #if defined(PETSC_HAVE_OPENGLES)
     15: #import <UIKit/UIKit.h>
     16: #import <GLKit/GLKit.h>
     17: #import <OpenGLES/EAGLDrawable.h>
     18: #import <OpenGLES/ES2/gl.h>
     19: #elif defined(PETSC_HAVE_GLUT)
     20: #if defined(__APPLE__) || defined(MACOSX)
     21: #include <AvailabilityMacros.h>
     22: #include <OpenGL/gl.h>
     23: #include <OpenGL/glu.h>
     24: #else
     25: #include <GL/gl.h>
     26: #include <GL/glu.h>
     27: #endif
     28: #endif

     31: /*
     32:      These macros transform from the users coordinates to the OpenGL coordinates of -1,-1 to 1,1.
     33: */
     34: #define XTRANS(draw,x)  (-1.0 + 2.0*((draw)->port_xl + (((x - (draw)->coor_xl)*((draw)->port_xr - (draw)->port_xl))/((draw)->coor_xr - (draw)->coor_xl))))
     35: #define YTRANS(draw,y)  (-1.0 + 2.0*((draw)->port_yl + (((y - (draw)->coor_yl)*((draw)->port_yr - (draw)->port_yl))/((draw)->coor_yr - (draw)->coor_yl))))

     37: /*
     38:      These macros transform from the users coordinates to pixel coordinates.
     39: */
     40: #define XPTRANS(draw,win,x) (int)(((win)->w)*((draw)->port_xl + (((x - (draw)->coor_xl)*((draw)->port_xr - (draw)->port_xl))/((draw)->coor_xr - (draw)->coor_xl))))
     41: #define YPTRANS(draw,win,y) (int)(((win)->h)*(1.0-(draw)->port_yl - (((y - (draw)->coor_yl)*((draw)->port_yr - (draw)->port_yl))/((draw)->coor_yr - (draw)->coor_yl))))

     43: static unsigned char rcolor[256],gcolor[256],bcolor[256];
     44: static PetscErrorCode InitializeColors(void)
     45: {

     49:   rcolor[PETSC_DRAW_WHITE]           = 255;
     50:   gcolor[PETSC_DRAW_WHITE]           = 255;
     51:   bcolor[PETSC_DRAW_WHITE]           = 255;
     52:   rcolor[PETSC_DRAW_BLACK]           =   0;
     53:   gcolor[PETSC_DRAW_BLACK]           =   0;
     54:   bcolor[PETSC_DRAW_BLACK]           =   0;
     55:   rcolor[PETSC_DRAW_RED]             = 255;
     56:   gcolor[PETSC_DRAW_RED]             =   0;
     57:   bcolor[PETSC_DRAW_RED]             =   0;
     58:   rcolor[PETSC_DRAW_GREEN]           =   0;
     59:   gcolor[PETSC_DRAW_GREEN]           = 128;
     60:   bcolor[PETSC_DRAW_GREEN]           =   0;
     61:   rcolor[PETSC_DRAW_CYAN]            =   0;
     62:   gcolor[PETSC_DRAW_CYAN]            = 139;
     63:   bcolor[PETSC_DRAW_CYAN]            = 139;
     64:   rcolor[PETSC_DRAW_BLUE]            =   0;
     65:   gcolor[PETSC_DRAW_BLUE]            =   0;
     66:   bcolor[PETSC_DRAW_BLUE]            = 255;
     67:   rcolor[PETSC_DRAW_MAGENTA]         = 255;
     68:   gcolor[PETSC_DRAW_MAGENTA]         =   0;
     69:   bcolor[PETSC_DRAW_MAGENTA]         = 255;
     70:   rcolor[PETSC_DRAW_AQUAMARINE]      = 127;
     71:   gcolor[PETSC_DRAW_AQUAMARINE]      = 255;
     72:   bcolor[PETSC_DRAW_AQUAMARINE]      = 212;
     73:   rcolor[PETSC_DRAW_FORESTGREEN]     =  34;
     74:   gcolor[PETSC_DRAW_FORESTGREEN]     = 139;
     75:   bcolor[PETSC_DRAW_FORESTGREEN]     =  34;
     76:   rcolor[PETSC_DRAW_ORANGE]          = 255;
     77:   gcolor[PETSC_DRAW_ORANGE]          = 165;
     78:   bcolor[PETSC_DRAW_ORANGE]          =   0;
     79:   rcolor[PETSC_DRAW_VIOLET]          = 238;
     80:   gcolor[PETSC_DRAW_VIOLET]          = 130;
     81:   bcolor[PETSC_DRAW_VIOLET]          = 238;
     82:   rcolor[PETSC_DRAW_BROWN]           = 165;
     83:   gcolor[PETSC_DRAW_BROWN]           =  42;
     84:   bcolor[PETSC_DRAW_BROWN]           =  42;
     85:   rcolor[PETSC_DRAW_PINK]            = 255;
     86:   gcolor[PETSC_DRAW_PINK]            = 192;
     87:   bcolor[PETSC_DRAW_PINK]            = 203;
     88:   rcolor[PETSC_DRAW_CORAL]           = 255;
     89:   gcolor[PETSC_DRAW_CORAL]           = 127;
     90:   bcolor[PETSC_DRAW_CORAL]           =  80;
     91:   rcolor[PETSC_DRAW_GRAY]            = 128;
     92:   gcolor[PETSC_DRAW_GRAY]            = 128;
     93:   bcolor[PETSC_DRAW_GRAY]            = 128;
     94:   rcolor[PETSC_DRAW_YELLOW]          = 255;
     95:   gcolor[PETSC_DRAW_YELLOW]          = 255;
     96:   bcolor[PETSC_DRAW_YELLOW]          =   0;
     97:   rcolor[PETSC_DRAW_GOLD]            = 255;
     98:   gcolor[PETSC_DRAW_GOLD]            = 215;
     99:   bcolor[PETSC_DRAW_GOLD]            =   0;
    100:   rcolor[PETSC_DRAW_LIGHTPINK]       = 255;
    101:   gcolor[PETSC_DRAW_LIGHTPINK]       = 182;
    102:   bcolor[PETSC_DRAW_LIGHTPINK]       = 193;
    103:   rcolor[PETSC_DRAW_MEDIUMTURQUOISE] =  72;
    104:   gcolor[PETSC_DRAW_MEDIUMTURQUOISE] = 209;
    105:   bcolor[PETSC_DRAW_MEDIUMTURQUOISE] = 204;
    106:   rcolor[PETSC_DRAW_KHAKI]           = 240;
    107:   gcolor[PETSC_DRAW_KHAKI]           = 230;
    108:   bcolor[PETSC_DRAW_KHAKI]           = 140;
    109:   rcolor[PETSC_DRAW_DIMGRAY]         = 105;
    110:   gcolor[PETSC_DRAW_DIMGRAY]         = 105;
    111:   bcolor[PETSC_DRAW_DIMGRAY]         = 105;
    112:   rcolor[PETSC_DRAW_YELLOWGREEN]     =  54;
    113:   gcolor[PETSC_DRAW_YELLOWGREEN]     = 205;
    114:   bcolor[PETSC_DRAW_YELLOWGREEN]     =  50;
    115:   rcolor[PETSC_DRAW_SKYBLUE]         = 135;
    116:   gcolor[PETSC_DRAW_SKYBLUE]         = 206;
    117:   bcolor[PETSC_DRAW_SKYBLUE]         = 235;
    118:   rcolor[PETSC_DRAW_DARKGREEN]       =   0;
    119:   gcolor[PETSC_DRAW_DARKGREEN]       = 100;
    120:   bcolor[PETSC_DRAW_DARKGREEN]       =   0;
    121:   rcolor[PETSC_DRAW_NAVYBLUE]        =   0;
    122:   gcolor[PETSC_DRAW_NAVYBLUE]        =   0;
    123:   bcolor[PETSC_DRAW_NAVYBLUE]        = 128;
    124:   rcolor[PETSC_DRAW_SANDYBROWN]      = 244;
    125:   gcolor[PETSC_DRAW_SANDYBROWN]      = 164;
    126:   bcolor[PETSC_DRAW_SANDYBROWN]      =  96;
    127:   rcolor[PETSC_DRAW_CADETBLUE]       =  95;
    128:   gcolor[PETSC_DRAW_CADETBLUE]       = 158;
    129:   bcolor[PETSC_DRAW_CADETBLUE]       = 160;
    130:   rcolor[PETSC_DRAW_POWDERBLUE]      = 176;
    131:   gcolor[PETSC_DRAW_POWDERBLUE]      = 224;
    132:   bcolor[PETSC_DRAW_POWDERBLUE]      = 230;
    133:   rcolor[PETSC_DRAW_DEEPPINK]        = 255;
    134:   gcolor[PETSC_DRAW_DEEPPINK]        =  20;
    135:   bcolor[PETSC_DRAW_DEEPPINK]        = 147;
    136:   rcolor[PETSC_DRAW_THISTLE]         = 216;
    137:   gcolor[PETSC_DRAW_THISTLE]         = 191;
    138:   bcolor[PETSC_DRAW_THISTLE]         = 216;
    139:   rcolor[PETSC_DRAW_LIMEGREEN]       =  50;
    140:   gcolor[PETSC_DRAW_LIMEGREEN]       = 205;
    141:   bcolor[PETSC_DRAW_LIMEGREEN]       =  50;
    142:   rcolor[PETSC_DRAW_LAVENDERBLUSH]   = 255;
    143:   gcolor[PETSC_DRAW_LAVENDERBLUSH]   = 240;
    144:   bcolor[PETSC_DRAW_LAVENDERBLUSH]   = 245;
    145:   rcolor[PETSC_DRAW_PLUM]            = 221;
    146:   gcolor[PETSC_DRAW_PLUM]            = 160;
    147:   bcolor[PETSC_DRAW_PLUM]            = 221;

    149:   PetscDrawUtilitySetCmap(NULL,256-PETSC_DRAW_BASIC_COLORS,rcolor+PETSC_DRAW_BASIC_COLORS,gcolor+PETSC_DRAW_BASIC_COLORS,bcolor+PETSC_DRAW_BASIC_COLORS);
    150:   return(0);
    151: }

    153: static GLuint vertexshader,fragmentshader,shaderprogram;
    154: static PetscErrorCode InitializeShader(void)
    155: {
    156:   const char *vertexsource = "attribute vec2 position;\
    157:                               attribute vec3 color; \
    158:                               varying vec4 vColor;\
    159:                               void main(void)\
    160:                               {\
    161:                                 vColor = vec4(color,0.50);\
    162:                                 gl_Position = vec4(position,0.0,1.0);\
    163:                               }\n";
    164: #if defined(PETSC_HAVE_GLUT)
    165:   const char *fragmentsource = "varying vec4 vColor;\
    166:                                 void main (void)\
    167:                                 {\
    168:                                   gl_FragColor = vColor; \
    169:                                 }\n";
    170: #else
    171:   const char *fragmentsource = "precision mediump float;\
    172:                                 varying vec4 vColor;\
    173:                                 void main (void)\
    174:                                 {\
    175:                                   gl_FragColor = vColor; \
    176:                                 }\n";
    177: #endif
    178:   int    isCompiled_VS, isCompiled_FS;
    179:   int    isLinked;
    180:   GLenum err;

    183:   /*  http://www.opengl.org/wiki/OpenGL_Shading_Language */
    184:   /* Create an empty vertex shader handle */
    185:   vertexshader = glCreateShader(GL_VERTEX_SHADER);

    187:   /* Send the vertex shader source code to GL */
    188:   /* Note that the source code is NULL character terminated. */
    189:   /* GL will automatically detect that therefore the length info can be 0 in this case (the last parameter) */
    190:   glShaderSource(vertexshader, 1, (const GLchar**)&vertexsource, 0);

    192:   /* Compile the vertex shader */
    193:   glCompileShader(vertexshader);
    194:   glGetShaderiv(vertexshader, GL_COMPILE_STATUS, &isCompiled_VS);
    195:   if (isCompiled_VS == GL_FALSE) {
    197:     int            maxLength;
    198:     char           *vertexInfoLog;
    199:     glGetShaderiv(vertexshader, GL_INFO_LOG_LENGTH, &maxLength);
    200:     PetscMalloc1(maxLength,&vertexInfoLog);
    201:     glGetShaderInfoLog(vertexshader, maxLength, &maxLength, vertexInfoLog);
    202:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile vertex shader %s",vertexInfoLog);
    203:   }

    205:   /* Create an empty fragment shader handle */
    206:   fragmentshader = glCreateShader(GL_FRAGMENT_SHADER);

    208:   /* Send the fragment shader source code to GL */
    209:   /* Note that the source code is NULL character terminated. */
    210:   /* GL will automatically detect that therefore the length info can be 0 in this case (the last parameter) */
    211:   glShaderSource(fragmentshader, 1, (const GLchar**)&fragmentsource, 0);

    213:   /* Compile the fragment shader */
    214:   glCompileShader(fragmentshader);
    215:   glGetShaderiv(fragmentshader, GL_COMPILE_STATUS, &isCompiled_FS);
    216:   if (isCompiled_FS == GL_FALSE) {
    218:     int            maxLength;
    219:     char           *fragmentInfoLog;
    220:     glGetShaderiv(fragmentshader, GL_INFO_LOG_LENGTH, &maxLength);
    221:     PetscMalloc1(maxLength,&fragmentInfoLog);
    222:     glGetShaderInfoLog(fragmentshader, maxLength, &maxLength, fragmentInfoLog);
    223:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile fragment shader %s",fragmentInfoLog);
    224:   }

    226:   /* If we reached this point it means the vertex and fragment shaders compiled and are syntax error free. */
    227:   /* We must link them together to make a GL shader program */
    228:   /* GL shader programs are monolithic. It is a single piece made of 1 vertex shader and 1 fragment shader. */
    229:   /* Assign our program handle a "name" */
    230:   shaderprogram = glCreateProgram();

    232:   /* Attach our shaders to our program */
    233:   glAttachShader(shaderprogram, vertexshader);
    234:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    235:   glAttachShader(shaderprogram, fragmentshader);
    236:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    238:   glBindAttribLocation(shaderprogram,0,"position");
    239:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    240:   glBindAttribLocation(shaderprogram,1,"color");
    241:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    243:   /* Link our program */
    244:   /* At this stage, the vertex and fragment programs are inspected, optimized and a binary code is generated for the shader. */
    245:   /* The binary code is uploaded to the GPU, if there is no error. */
    246:   glLinkProgram(shaderprogram);

    248:   /* Again, we must check and make sure that it linked. If it fails, it would mean either there is a mismatch between the vertex */
    249:   /* and fragment shaders. It might be that you have surpassed your GPU's abilities. Perhaps too many ALU operations or */
    250:   /* too many texel fetch instructions or too many interpolators or dynamic loops. */

    252:   glGetProgramiv(shaderprogram, GL_LINK_STATUS, &isLinked);
    253:   if (isLinked == GL_FALSE) {
    254:     /*
    255:     char          *shaderProgramInfoLog;
    256:     glGetProgramiv(shaderprogram, GL_INFO_LOG_LENGTH, &maxLength);
    257:     shaderProgramInfoLog = new char[maxLength];
    258:     glGetProgramInfoLog(shaderprogram, maxLength, &maxLength, shaderProgramInfoLog);
    259:     free(shaderProgramInfoLog);
    260:     */
    261:     SETERRQ(PETSC_COMM_SELF,PETSC_ERR_LIB,"Failed to compile fragment shader");
    262:   }

    264:   /* In your rendering code, you just need to call glUseProgram, call the various glUniform** to update your uniforms */
    265:   /* and then render. */
    266:   /* Load the shader into the rendering pipeline */
    267:   glUseProgram(shaderprogram);
    268:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    269:   return(0);
    270: }

    272: /*
    273:     This is currently all wrong, there is actually a separate shader for each window
    274:    so they cannot be stored as global
    275: */
    276: static PetscErrorCode FinalizeShader(void)
    277: {
    279:   /* When the user shuts down your program, you should deallocate all your GL resources. */
    280:   /* Unbind your shader. */
    281:   glUseProgram(0);
    282:   /* Let's detach */
    283:   glDetachShader(shaderprogram, vertexshader);
    284:   glDetachShader(shaderprogram, fragmentshader);
    285:   /* Delete the shaders */
    286:   glDeleteShader(vertexshader);
    287:   glDeleteShader(fragmentshader);
    288:   /* Delete the shader object */
    289:   glDeleteProgram(shaderprogram);
    290:   return(0);
    291: }

    293: PETSC_INTERN PetscErrorCode PetscDrawClear_OpenGL_Base(PetscDraw);

    295: #if defined(PETSC_HAVE_GLUT)
    296: #include <GLUT/glut.h>
    297: typedef struct {
    298:   int win;           /* OpenGL GLUT window identifier */
    299:   int x,y,w,h;       /* Size and location of window */
    300: } PetscDraw_OpenGL;

    302: static int currentwindow = -1;
    303: PETSC_STATIC_INLINE PetscErrorCode OpenGLWindow(PetscDraw_OpenGL *win)
    304: {
    305:   if (win->win == currentwindow) return 0;
    306:   currentwindow = win->win;
    307:   glutSetWindow(win->win);
    308:   return 0;
    309: }

    311: PETSC_STATIC_INLINE PetscErrorCode OpenGLString(float x,float y, const char *str,size_t len,int icolor)
    312: {
    313:   PetscInt i;

    315:   glColor3ub(rcolor[icolor],gcolor[icolor],bcolor[icolor]);
    316:   glRasterPos2f(x, y);
    317:   for (i = 0; i < len; i++) glutBitmapCharacter(GLUT_BITMAP_8_BY_13, str[i]);
    318:   return 0;
    319: }

    321: PetscErrorCode PetscDrawClear_OpenGL(PetscDraw draw)
    322: {

    326:   PetscDrawClear_OpenGL_Base(draw);
    327:   return(0);
    328: }

    330: static PetscErrorCode PetscDrawGetPopup_OpenGL(PetscDraw draw,PetscDraw *popup)
    331: {

    335:   PetscDrawCreate(PetscObjectComm((PetscObject)draw),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,popup);
    336:   PetscDrawSetType(*popup,((PetscObject)draw)->type_name);

    338:   draw->popup = *popup;
    339:   return(0);
    340: }

    342: static PetscErrorCode PetscDrawStringVertical_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    343: {
    344:   PetscErrorCode   ierr;
    345:   float            xx,yy;
    346:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    347:   PetscReal        tw,th;
    348:   size_t           i,n;

    351:   OpenGLWindow(win);
    352:   PetscStrlen(chrs,&n);
    353:   PetscDrawStringGetSize(draw,&tw,&th);
    354:   xx   = XTRANS(draw,x);
    355:   for (i=0; i<n; i++) {
    356:     yy   = YTRANS(draw,y-th*i);
    357:     OpenGLString(xx,yy,chrs+i,1,c);
    358:   }
    359:   return(0);
    360: }

    362: static PetscErrorCode PetscDrawString_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    363: {
    364:   PetscErrorCode   ierr;
    365:   float            xx,yy;
    366:   size_t           len;
    367:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    368:   char             *substr;
    369:   PetscToken       token;

    372:   xx   = XTRANS(draw,x);
    373:   yy   = YTRANS(draw,y);
    374:   OpenGLWindow(win);

    376:   PetscTokenCreate(chrs,'\n',&token);
    377:   PetscTokenFind(token,&substr);
    378:   PetscStrlen(substr,&len);
    379:   OpenGLString(xx,yy,substr,len,c);
    380:   PetscTokenFind(token,&substr);
    381:   while (substr) {
    382:     yy  += 16;
    383:     PetscStrlen(substr,&len);
    384:     OpenGLString(xx,yy,substr,len,c);
    385:     PetscTokenFind(token,&substr);
    386:   }
    387:   PetscTokenDestroy(&token);
    388:   return(0);
    389: }

    391: static PetscErrorCode PetscDrawSetTitle_OpenGL(PetscDraw draw,const char title[])
    392: {
    393:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    394:   PetscErrorCode   ierr;

    397:   OpenGLWindow(win);
    398:   glutSetWindowTitle(title);
    399:   return(0);
    400: }

    402: static PetscErrorCode PetscDrawDestroy_OpenGL(PetscDraw draw)
    403: {
    404:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    405:   PetscErrorCode   ierr;

    408:   PetscDrawClear(draw);
    409:   PetscDrawDestroy(&draw->popup);
    410:   glutDestroyWindow(win->win);
    411:   PetscFree(draw->data);
    412:   return(0);
    413: }

    415: static PetscErrorCode PetscDrawFlush_OpenGL(PetscDraw draw)
    416: {
    417:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    418:   PetscErrorCode   ierr;

    421:   OpenGLWindow(win);
    422:   glutCheckLoop();
    423:   glFinish();
    424:   return(0);
    425: }

    427: static PetscErrorCode PetscDrawStringGetSize_OpenGL(PetscDraw draw,PetscReal *x,PetscReal  *y)
    428: {
    429:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    430:   PetscInt         w;
    431:   PetscErrorCode   ierr;

    434:   OpenGLWindow(win);
    435:   w    = glutBitmapWidth(GLUT_BITMAP_8_BY_13,'W');
    436:   if (x) *x   = w*(draw->coor_xr - draw->coor_xl)/((win->w)*(draw->port_xr - draw->port_xl));
    437:   if (y) *y   = (13./8.0)*w*(draw->coor_yr - draw->coor_yl)/((win->h)*(draw->port_yr - draw->port_yl));
    438:   return(0);
    439: }

    441: static PetscErrorCode PetscDrawResizeWindow_OpenGL(PetscDraw draw,int w,int h)
    442: {
    443:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    444:   PetscErrorCode   ierr;

    447:   OpenGLWindow(win);
    448:   glutReshapeWindow(w,h);
    449:   PetscDrawFlush(draw);
    450:   PetscDrawCheckResizedWindow(draw);
    451:   return(0);
    452: }

    454: static PetscBool resized = PETSC_FALSE;

    456: static PetscErrorCode PetscDrawCheckResizedWindow_OpenGL(PetscDraw draw)
    457: {

    461:   if (!resized) return(0);
    462:   resized = PETSC_FALSE;
    463:   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    464:   PetscDrawClear(draw);
    465:   return(0);
    466: }

    468: typedef struct {
    469:   int button,x,y;
    470: } OpenGLButton;
    471: static OpenGLButton Mouse;

    473: static PetscErrorCode PetscDrawGetMouseButton_OpenGL(PetscDraw draw,PetscDrawButton *button,PetscReal *x_user,PetscReal *y_user,PetscReal *x_phys,PetscReal *y_phys)
    474: {
    475:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    476:   int              px,py;

    479:   while (Mouse.button == -1) glutCheckLoop();

    481:   *button      = (PetscDrawButton)(Mouse.button + 1);
    482:   px           = Mouse.x;
    483:   py           = Mouse.y;
    484:   Mouse.button = -1;

    486:   if (x_phys) *x_phys = ((double)px)/((double)win->w);
    487:   if (y_phys) *y_phys = 1.0 - ((double)py)/((double)win->h);

    489:   if (x_user) *x_user = draw->coor_xl + ((((double)px)/((double)win->w)-draw->port_xl))*(draw->coor_xr - draw->coor_xl)/(draw->port_xr - draw->port_xl);
    490:   if (y_user) *y_user = draw->coor_yl + ((1.0 - ((double)py)/((double)win->h)-draw->port_yl))*(draw->coor_yr - draw->coor_yl)/(draw->port_yr - draw->port_yl);
    491:   return(0);
    492: }
    493: #elif defined(PETSC_HAVE_OPENGLES)
    494: typedef struct {
    495:   GLint   win;    /* not currently used */
    496:   int     w,h;    /* width and height in pixels */
    497:   int     view;
    498: } PetscDraw_OpenGL;

    500: static GLKView *globalGLKView[10] = {0,0,0,0,0,0,0,0,0,0};
    501: static int     globalGLKViewUsed[10]  = {0,0,0,0,0,0,0,0,0,0};
    502: PETSC_STATIC_INLINE PetscErrorCode OpenGLWindow(PetscDraw_OpenGL *win)
    503: {
    504:   return 0;
    505: }

    507: static PetscErrorCode PetscDrawClear_OpenGL(PetscDraw draw)
    508: {
    509:   PetscErrorCode   ierr;
    510:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;

    513:   /* remove all UIText added to window */
    514:   for (UIView *view in [globalGLKView[win->view] subviews]) {[view removeFromSuperview];}
    515:   PetscDrawClear_OpenGL_Base(draw);
    516:   return(0);
    517: }

    519: static PetscErrorCode PetscDrawGetPopup_OpenGL(PetscDraw draw,PetscDraw *popup)
    520: {

    524:   *popup = NULL;
    525:   return(0);
    526: }

    528: static PetscErrorCode PetscDrawString_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    529: {
    530:   PetscErrorCode   ierr;
    531:   float            xx,yy;
    532:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    533:   UILabel          *yourLabel;

    536:   OpenGLWindow(win);
    537:   xx   = XPTRANS(draw,win,x);
    538:   yy   = YPTRANS(draw,win,y);
    539:   NSLog(@"Draw string start");
    540:   yourLabel = [[UILabel alloc] initWithFrame:CGRectMake(xx, yy, 300, 20)];
    541:   [yourLabel setTextColor:[UIColor colorWithRed:rcolor[c]/255.0 green:gcolor[c]/255.0 blue:rcolor[c]/255.0 alpha:1.0]];
    542:   [yourLabel setText: [[NSString alloc] initWithCString:chrs encoding:NSMacOSRomanStringEncoding]];
    543:   [yourLabel setBackgroundColor:[UIColor clearColor]];
    544:   /* [yourLabel setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]]; */
    545:   [globalGLKView[win->view] addSubview:yourLabel];
    546:   NSLog(@"Draw string end");
    547:   return(0);
    548: }

    550: /*
    551:    I don't understand the rotation. It seems to maybe rotate from the middle of the width?

    553:    It would be nice if the frame could be made to match the text length automatically

    555:    This makes src/sys/draw/examples/tests/ex3.c look good but may be terrible for other locations
    556: */
    557: static PetscErrorCode PetscDrawStringVertical_OpenGL(PetscDraw draw,PetscReal x,PetscReal y,int c,const char chrs[])
    558: {
    559:   PetscErrorCode   ierr;
    560:   float            xx,yy, w = 100,h = 20;
    561:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    562:   UILabel          *yourLabel;

    565:   OpenGLWindow(win);
    566:   xx   = XPTRANS(draw,win,x);
    567:   yy   = YPTRANS(draw,win,y);
    568:   NSLog(@"Draw string vertical start");
    569:   yourLabel = [[UILabel alloc] initWithFrame:CGRectMake(0,0, w, h)];
    570:   [yourLabel setTextColor:[UIColor colorWithRed:rcolor[c]/255.0 green:gcolor[c]/255.0 blue:rcolor[c]/255.0 alpha:1.0]];
    571:   [yourLabel setText: [[NSString alloc] initWithCString:chrs encoding:NSMacOSRomanStringEncoding]];
    572:   [yourLabel setBackgroundColor:[UIColor clearColor]];
    573:   [yourLabel setTransform:CGAffineTransformTranslate(CGAffineTransformMakeRotation(-PETSC_PI / 2),-w/2.0-yy,-h+xx)];
    574:   /* [yourLabel setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]]; */
    575:   [globalGLKView[win->view] addSubview:yourLabel];
    576:   NSLog(@"Draw string vertical end");
    577:   return(0);
    578: }

    580: static PetscErrorCode PetscDrawSetTitle_OpenGL(PetscDraw draw,const char title[])
    581: {
    582:   return 0;
    583: }
    584: static PetscErrorCode PetscDrawDestroy_OpenGL(PetscDraw draw)
    585: {
    586:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    587:   PetscErrorCode   ierr;
    588:   PetscInt         i;

    591:   globalGLKViewUsed[win->view] = 0;
    592:   PetscFree(draw->data);
    593:   return(0);
    594:   return(0);
    595: }
    596: static PetscErrorCode PetscDrawFlush_OpenGL(PetscDraw draw)
    597: {
    598:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;

    600:   GLenum err;
    601:   glFlush();
    602:   err = glGetError();
    603:   if (err != GL_NO_ERROR) {
    604:     NSLog(@"GL error detected glFlush()");
    605:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Unable to flush OpenGL Error Code %d",err);
    606:   }
    607:   [globalGLKView[win->view] display];
    608:   NSLog(@"Completed display in PetscDrawFlush()");
    609:   return 0;
    610: }
    611: static PetscErrorCode PetscDrawStringGetSize_OpenGL(PetscDraw draw,PetscReal *x,PetscReal  *y)
    612: {
    613:   float w = .02;
    614:   if (x) *x = w*(draw->coor_xr - draw->coor_xl)/(draw->port_xr - draw->port_xl);
    615:   if (y) *y = (13./8.0)*w*(draw->coor_yr - draw->coor_yl)/(draw->port_yr - draw->port_yl);
    616:   return 0;
    617: }
    618: static PetscErrorCode PetscDrawResizeWindow_OpenGL(PetscDraw draw,int w,int h)
    619: {
    620:   return 0;
    621: }
    622: static PetscErrorCode PetscDrawCheckResizedWindow_OpenGL(PetscDraw draw)
    623: {
    624:   return 0;
    625: }
    626: static PetscErrorCode PetscDrawGetMouseButton_OpenGL(PetscDraw draw,PetscDrawButton *button,PetscReal *x_user,PetscReal *y_user,PetscReal *x_phys,PetscReal *y_phys)
    627: {
    628:   return 0;
    629: }
    630: #endif

    632: /* -----------------------------------------------------------------------*/

    634: PetscErrorCode PetscDrawClear_OpenGL_Base(PetscDraw draw)
    635: {
    636:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    637:   PetscErrorCode   ierr;
    638:   float            xl,yl,xr,yr;
    639:   GLfloat          vertices[12];
    640:   GLfloat          colors[18];
    641:   GLuint           positionBufferObject;
    642:   GLuint           colorBufferObject;
    643:   GLenum           err;

    646:   OpenGLWindow(win);
    647:   xl   = -1.0 + 2.0*((draw)->port_xl);
    648:   xr   = -1.0 + 2.0*((draw)->port_xr);
    649:   yl   = -1.0 + 2.0*((draw)->port_yl);
    650:   yr   = -1.0 + 2.0*((draw)->port_yr);

    652:   vertices[0] = xl;
    653:   vertices[1] = yl;
    654:   vertices[2] = xr;
    655:   vertices[3] = yl;
    656:   vertices[4] = xl;
    657:   vertices[5] = yr;

    659:   vertices[6]  = xl;
    660:   vertices[7]  = yr;
    661:   vertices[8]  = xr;
    662:   vertices[9]  = yr;
    663:   vertices[10] = xr;
    664:   vertices[11] = yl;

    666:   colors[0] = 1.0;  colors[1] = 1.0; colors[2] = 1.0;
    667:   colors[3] = 1.0;  colors[4] = 1.0; colors[5] = 1.0;
    668:   colors[6] = 1.0;  colors[7] = 1.0; colors[8] = 1.0;

    670:   colors[9]  = 1.0;  colors[10] = 1.0; colors[11] = 1.0;
    671:   colors[12] = 1.0;  colors[13] = 1.0; colors[14] = 1.0;
    672:   colors[15] = 1.0;  colors[16] = 1.0; colors[17] = 1.0;

    674:   glGenBuffers(1, &positionBufferObject);
    675:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    676:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    677:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    678:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    679:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    680:   glEnableVertexAttribArray(0);
    681:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    682:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    683:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    685:   glGenBuffers(1, &colorBufferObject);
    686:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    687:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    688:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    689:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    690:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    691:   glEnableVertexAttribArray(1);
    692:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    693:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    694:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    696:   glDrawArrays(GL_TRIANGLES, 0, 6);
    697:   glDisableVertexAttribArray(0);
    698:   glDisableVertexAttribArray(1);
    699:   glDeleteBuffers(1, &positionBufferObject);
    700:   glDeleteBuffers(1, &colorBufferObject);
    701:   PetscDrawFlush(draw);
    702:   return(0);
    703: }

    705: static PetscErrorCode PetscDrawPoint_OpenGL(PetscDraw draw,PetscReal xl,PetscReal yl,int cl)
    706: {
    707:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    708:   GLfloat          vertices[2],colors[3];
    709:   PetscErrorCode   ierr;
    710:   GLuint           positionBufferObject;
    711:   GLuint           colorBufferObject;
    712:   GLenum           err;

    715:   vertices[0] = XTRANS(draw,xl);
    716:   vertices[1] = YTRANS(draw,yl);
    717:   colors[0]   = rcolor[cl]/255.0;  colors[1] = gcolor[cl]/255.0; colors[2] = bcolor[cl]/255.0;

    719:   OpenGLWindow(win);
    720:   glGenBuffers(1, &positionBufferObject);
    721:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    722:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    723:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    724:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    725:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    726:   glEnableVertexAttribArray(0);
    727:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    728:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    729:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    731:   glGenBuffers(1, &colorBufferObject);
    732:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    733:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    734:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    735:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    736:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    737:   glEnableVertexAttribArray(1);
    738:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    739:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    740:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    742:   glDrawArrays(GL_POINTS, 0, 2);
    743:   glDisableVertexAttribArray(0);
    744:   glDisableVertexAttribArray(1);
    745:   glDeleteBuffers(1, &positionBufferObject);
    746:   glDeleteBuffers(1, &colorBufferObject);
    747:   return(0);
    748: }

    750: static PetscErrorCode PetscDrawLine_OpenGL(PetscDraw draw,PetscReal xl,PetscReal yl,PetscReal xr,PetscReal yr,int cl)
    751: {
    752:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    753:   GLfloat          linevertices[4],colors[6];
    754:   PetscErrorCode   ierr;
    755:   GLenum           err;
    756:   GLuint           positionBufferObject;
    757:   GLuint           colorBufferObject;

    761:   linevertices[0] = XTRANS(draw,xl);
    762:   linevertices[2] = XTRANS(draw,xr);
    763:   linevertices[1] = YTRANS(draw,yl);
    764:   linevertices[3] = YTRANS(draw,yr);
    765:   if (linevertices[0] == linevertices[2] && linevertices[1] == linevertices[3]) return(0);
    766:   colors[0] = rcolor[cl]/255.0;  colors[1] = gcolor[cl]/255.0; colors[2] = bcolor[cl]/255.0;
    767:   colors[3] = rcolor[cl]/255.0;  colors[4] = gcolor[cl]/255.0; colors[5] = bcolor[cl]/255.0;

    769:   OpenGLWindow(win);
    770:   /* http://arcsynthesis.org/gltut/Basics/Tutorial%2001.html */
    771:   glGenBuffers(1, &positionBufferObject);
    772:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    773:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    774:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    775:   glBufferData(GL_ARRAY_BUFFER, sizeof(linevertices), linevertices, GL_STATIC_DRAW);
    776:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    777:   glEnableVertexAttribArray(0);
    778:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    779:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    780:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    782:   glGenBuffers(1, &colorBufferObject);
    783:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    784:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    785:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    786:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    787:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    788:   glEnableVertexAttribArray(1);
    789:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    790:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    791:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    793:   glDrawArrays(GL_LINES, 0, 2);
    794:   glDisableVertexAttribArray(0);
    795:   glDisableVertexAttribArray(1);
    796:   glDeleteBuffers(1, &positionBufferObject);
    797:   glDeleteBuffers(1, &colorBufferObject);
    798:   return(0);
    799: }

    801: static PetscErrorCode PetscDrawTriangle_OpenGL(PetscDraw draw,PetscReal X1,PetscReal Y_1,PetscReal X2,PetscReal Y2,PetscReal X3,PetscReal Y3,int c1,int c2,int c3)
    802: {
    803:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    804:   PetscErrorCode   ierr;
    805:   GLfloat          vertices[6],colors[9];
    806:   GLenum           err;
    807:   GLuint           positionBufferObject;
    808:   GLuint           colorBufferObject;

    811:   vertices[0] = XTRANS(draw,X1);
    812:   vertices[1] = YTRANS(draw,Y_1);
    813:   vertices[2] = XTRANS(draw,X2);
    814:   vertices[3] = YTRANS(draw,Y2);
    815:   vertices[4] = XTRANS(draw,X3);
    816:   vertices[5] = YTRANS(draw,Y3);
    817:   colors[0]   = rcolor[c1]/255.0;  colors[1] = gcolor[c1]/255.0; colors[2] = bcolor[c1]/255.0;
    818:   colors[3]   = rcolor[c2]/255.0;  colors[4] = gcolor[c2]/255.0; colors[5] = bcolor[c2]/255.0;
    819:   colors[6]   = rcolor[c3]/255.0;  colors[7] = gcolor[c3]/255.0; colors[8] = bcolor[c3]/255.0;

    821:   OpenGLWindow(win);
    822:   glGenBuffers(1, &positionBufferObject);
    823:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    824:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    825:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    826:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    827:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    828:   glEnableVertexAttribArray(0);
    829:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    830:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    831:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    833:   glGenBuffers(1, &colorBufferObject);
    834:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    835:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    836:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    837:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    838:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    839:   glEnableVertexAttribArray(1);
    840:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    841:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    842:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    844:   glDrawArrays(GL_TRIANGLES, 0, 3);
    845:   glDisableVertexAttribArray(0);
    846:   glDisableVertexAttribArray(1);
    847:   glDeleteBuffers(1, &positionBufferObject);
    848:   glDeleteBuffers(1, &colorBufferObject);
    849:   return(0);
    850: }

    852: static PetscErrorCode PetscDrawRectangle_OpenGL(PetscDraw draw,PetscReal Xl,PetscReal Yl,PetscReal Xr,PetscReal Yr,int c1,int c2,int c3,int c4)
    853: {
    854:   PetscDraw_OpenGL *win = (PetscDraw_OpenGL*)draw->data;
    855:   PetscErrorCode   ierr;
    856:   GLfloat          vertices[12],colors[18];
    857:   float            x1,y_1,x2,y2;
    858:   GLuint           positionBufferObject;
    859:   GLuint           colorBufferObject;
    860:   GLenum           err;

    863:   x1  = XTRANS(draw,Xl);
    864:   y_1 = YTRANS(draw,Yl);
    865:   x2  = XTRANS(draw,Xr);
    866:   y2  = YTRANS(draw,Yr);

    868:   OpenGLWindow(win);

    870:   vertices[0] = x1; colors[0] = rcolor[c1]/255.0;  colors[1] = gcolor[c1]/255.0; colors[2] = bcolor[c1]/255.0;
    871:   vertices[1] = y_1;
    872:   vertices[2] = x2;colors[3] = rcolor[c2]/255.0;  colors[4] = gcolor[c2]/255.0; colors[5] = bcolor[c2]/255.0;
    873:   vertices[3] = y_1;
    874:   vertices[4] = x1;colors[6] = rcolor[c4]/255.0;  colors[7] = gcolor[c4]/255.0; colors[8] = bcolor[c4]/255.0;
    875:   vertices[5] = y2;

    877:   vertices[6]  = x1;colors[9] = rcolor[c4]/255.0;  colors[10] = gcolor[c4]/255.0; colors[11] = bcolor[c4]/255.0;
    878:   vertices[7]  = y2;
    879:   vertices[8]  = x2;colors[12] = rcolor[c3]/255.0;  colors[13] = gcolor[c3]/255.0; colors[14] = bcolor[c3]/255.0;
    880:   vertices[9]  = y2;
    881:   vertices[10] = x2;colors[15] = rcolor[c2]/255.0;  colors[16] = gcolor[c2]/255.0; colors[17] = bcolor[c2]/255.0;
    882:   vertices[11] = y_1;

    884:   glGenBuffers(1, &positionBufferObject);
    885:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    886:   glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    887:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    888:   glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
    889:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    890:   glEnableVertexAttribArray(0);
    891:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    892:   glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, 0);
    893:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    895:   glGenBuffers(1, &colorBufferObject);
    896:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    897:   glBindBuffer(GL_ARRAY_BUFFER, colorBufferObject);
    898:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    899:   glBufferData(GL_ARRAY_BUFFER, sizeof(colors), colors, GL_STATIC_DRAW);
    900:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    901:   glEnableVertexAttribArray(1);
    902:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);
    903:   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    904:   err = glGetError(); if (err) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"OpenGL error %d\n",err);

    906:   glDrawArrays(GL_TRIANGLES, 0, 6);
    907:   glDisableVertexAttribArray(0);
    908:   glDisableVertexAttribArray(1);
    909:   glDeleteBuffers(1, &positionBufferObject);
    910:   glDeleteBuffers(1, &colorBufferObject);
    911:   return(0);
    912: }

    915: static PetscErrorCode PetscDrawPause_OpenGL(PetscDraw draw)
    916: {

    920:   if (draw->pause > 0) PetscSleep(draw->pause);
    921:   else if (draw->pause == -1) {
    922:     PetscDrawButton button = PETSC_BUTTON_NONE;
    923:     PetscDrawGetMouseButton(draw,&button,0,0,0,0);
    924:     if (button == PETSC_BUTTON_CENTER) draw->pause = 0;
    925:   }
    926:   return(0);
    927: }

    930: static struct _PetscDrawOps DvOps = { 0,
    931:                                       PetscDrawFlush_OpenGL,
    932:                                       PetscDrawLine_OpenGL,
    933:                                       0,
    934:                                       0,
    935:                                       PetscDrawPoint_OpenGL,
    936:                                       0,
    937:                                       PetscDrawString_OpenGL,
    938:                                       PetscDrawStringVertical_OpenGL,
    939:                                       0, /* PetscDrawStringSetSize_OpenGL,*/
    940:                                       PetscDrawStringGetSize_OpenGL,
    941:                                       0, /* PetscDrawSetViewport_OpenGL,*/
    942:                                       PetscDrawClear_OpenGL,
    943:                                       PetscDrawRectangle_OpenGL,
    944:                                       PetscDrawTriangle_OpenGL,
    945:                                       0, /* PetscDrawEllipse_OpenGL,*/
    946:                                       PetscDrawGetMouseButton_OpenGL,
    947:                                       PetscDrawPause_OpenGL,
    948:                                       0,
    949:                                       0,
    950:                                       PetscDrawGetPopup_OpenGL,
    951:                                       PetscDrawSetTitle_OpenGL,
    952:                                       PetscDrawCheckResizedWindow_OpenGL,
    953:                                       PetscDrawResizeWindow_OpenGL,
    954:                                       PetscDrawDestroy_OpenGL,
    955:                                       0,
    956:                                       0, /* PetscDrawGetSingleton_OpenGL,*/
    957:                                       0, /* PetscDrawRestoreSingleton_OpenGL,*/
    958:                                       0,
    959:                                       0,
    960:                                       0,
    961:                                       PetscDrawLine_OpenGL};

    963: #if defined(PETSC_HAVE_GLUT)
    964: /* callbacks required by GLUT */
    965: static void display(void) {;}
    966: static void reshape(int width, int height)
    967: {
    968:   glViewport(0, 0, width, height);
    969:   resized = PETSC_TRUE;
    970: }
    971: static void mouse(int button, int state,int x, int y)
    972: {
    973:   if (state == GLUT_UP) {
    974:     Mouse.button = button;
    975:     Mouse.x      = x;
    976:     Mouse.y      = y;
    977:   }
    978: }

    980: PETSC_EXTERN PetscErrorCode PetscDrawCreate_GLUT(PetscDraw draw)
    981: {
    982:   PetscDraw_OpenGL *win;
    983:   PetscErrorCode   ierr;
    984:   PetscInt         xywh[4],osize = 4;
    985:   int              x = draw->x,y = draw->y,w = draw->w,h = draw->h;
    986:   static int       xavailable = 0,yavailable = 0,xmax = 0,ymax = 0,ybottom = 0;
    987:   static PetscBool initialized = PETSC_FALSE;
    988:   int              argc;
    989:   char             **argv;

    992:   if (!initialized) {
    993:     PetscGetArgs(&argc,&argv);
    994:     glutInit(&argc, argv);
    995:     glutInitDisplayMode(GLUT_RGBA /* | GLUT_DOUBLE */| GLUT_DEPTH);
    996:     InitializeColors();
    997:   }

    999:   /*
    1000:       Initialize the display size
    1001:   */
    1002:   if (!xmax) {
    1003:     xmax = glutGet(GLUT_SCREEN_WIDTH);
    1004:     ymax = glutGet(GLUT_SCREEN_HEIGHT);
    1005:   }

    1007:   if (w == PETSC_DECIDE) w = draw->w = 300;
    1008:   if (h == PETSC_DECIDE) h = draw->h = 300;
    1009:   switch (w) {
    1010:   case PETSC_DRAW_FULL_SIZE: w = draw->w = xmax - 10; break;
    1011:   case PETSC_DRAW_HALF_SIZE: w = draw->w = (xmax - 20)/2; break;
    1012:   case PETSC_DRAW_THIRD_SIZE: w = draw->w = (xmax - 30)/3; break;
    1013:   case PETSC_DRAW_QUARTER_SIZE: w = draw->w = (xmax - 40)/4; break;
    1014:   }
    1015:   switch (h) {
    1016:   case PETSC_DRAW_FULL_SIZE: h = draw->h = ymax - 10; break;
    1017:   case PETSC_DRAW_HALF_SIZE: h = draw->h = (ymax - 20)/2; break;
    1018:   case PETSC_DRAW_THIRD_SIZE: h = draw->h = (ymax - 30)/3; break;
    1019:   case PETSC_DRAW_QUARTER_SIZE: h = draw->h = (ymax - 40)/4; break;
    1020:   }

    1022:   /* allow user to set location and size of window */
    1023:   xywh[0] = x; xywh[1] = y; xywh[2] = w; xywh[3] = h;
    1024:   PetscOptionsGetIntArray(NULL,"-geometry",xywh,&osize,NULL);
    1025:   x       = (int) xywh[0]; y = (int) xywh[1]; w = (int) xywh[2]; h = (int) xywh[3];

    1028:   if (draw->x == PETSC_DECIDE || draw->y == PETSC_DECIDE) {
    1029:     /*
    1030:        PETSc tries to place windows starting in the upper left corner and
    1031:        moving across to the right.

    1033:               --------------------------------------------
    1034:               |  Region used so far +xavailable,yavailable |
    1035:               |                     +                      |
    1036:               |                     +                      |
    1037:               |++++++++++++++++++++++ybottom               |
    1038:               |                                            |
    1039:               |                                            |
    1040:               |--------------------------------------------|
    1041:     */
    1042:     /*  First: can we add it to the right? */
    1043:     if (xavailable+w+10 <= xmax) {
    1044:       x       = xavailable;
    1045:       y       = yavailable;
    1046:       ybottom = PetscMax(ybottom,y + h + 30);
    1047:     } else {
    1048:       /* No, so add it below on the left */
    1049:       xavailable = 0;
    1050:       x          = 0;
    1051:       yavailable = ybottom;
    1052:       y          = ybottom;
    1053:       ybottom    = ybottom + h + 30;
    1054:     }
    1055:   }
    1056:   /* update available region */
    1057:   xavailable = PetscMax(xavailable,x + w + 10);
    1058:   if (xavailable >= xmax) {
    1059:     xavailable = 0;
    1060:     yavailable = yavailable + h + 30;
    1061:     ybottom    = yavailable;
    1062:   }
    1063:   if (yavailable >= ymax) {
    1064:     y          = 0;
    1065:     yavailable = 0;
    1066:     ybottom    = 0;
    1067:   }

    1069:   PetscMemcpy(draw->ops,&DvOps,sizeof(DvOps));

    1071:   /* actually create and open the window */
    1072:   PetscNew(&win);
    1073:   PetscLogObjectMemory((PetscObject)draw,sizeof(PetscDraw_OpenGL));

    1075:   if (x < 0 || y < 0)   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative corner of window");
    1076:   if (w <= 0 || h <= 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative window width or height");

    1078:   win->x = x;
    1079:   win->y = y;
    1080:   win->w = w;
    1081:   win->h = h;

    1083:   glutInitWindowSize(w, h);
    1084:   glutInitWindowPosition(x,y);
    1085:   win->win = glutCreateWindow(draw->title);
    1086:   glutDisplayFunc(display);
    1087:   glutReshapeFunc(reshape);
    1088:   Mouse.button = -1;
    1089:   Mouse.x      = -1;
    1090:   Mouse.y      = -1;
    1091:   glutMouseFunc(mouse);

    1093:   glClearColor(1.0,1.0,1.0,1.0);

    1095:   draw->data = win;
    1096:   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    1097:   InitializeShader();

    1099:   PetscDrawClear(draw);
    1100:   resized = PETSC_FALSE; /* opening the window triggers OpenGL call to reshape so need to cancel that resized flag */
    1101:   glutCheckLoop();
    1102:   return(0);
    1103: }

    1105: /*@C
    1106:    PetscDrawOpenGLUT - Opens an OpenGL window based on GLUT for use with the PetscDraw routines.

    1108:    Collective on MPI_Comm

    1110:    Input Parameters:
    1111: +  comm - the communicator that will share X-window
    1112: .  display - the X display on which to open,or null for the local machine
    1113: .  title - the title to put in the title bar,or null for no title
    1114: .  x,y - the screen coordinates of the upper left corner of window
    1115:           may use PETSC_DECIDE for these two arguments, then PETSc places the
    1116:           window
    1117: -  w, h - the screen width and height in pixels,  or PETSC_DRAW_HALF_SIZE, PETSC_DRAW_FULL_SIZE,
    1118:           or PETSC_DRAW_THIRD_SIZE or PETSC_DRAW_QUARTER_SIZE

    1120:    Output Parameters:
    1121: .  draw - the drawing context.

    1123:    Options Database Keys:
    1124: +  -nox - Disables all x-windows output
    1125: .  -draw_pause <pause> - Sets time (in seconds) that the
    1126:        program pauses after PetscDrawPause() has been called
    1127:        (0 is default, -1 implies until user input).
    1128: .  -draw_cmap <name> - Sets the colormap to use.
    1129: .  -draw_cmap_reverse - Reverses the colormap.
    1130: -  -draw_cmap_brighten - Brighten (0 < beta < 1) or darken (-1 < beta < 0) the colormap.

    1132:    Level: beginner

    1134:    Note:
    1135:    When finished with the drawing context, it should be destroyed
    1136:    with PetscDrawDestroy().

    1138:    Note for Fortran Programmers:
    1139:    Whenever indicating null character data in a Fortran code,
    1140:    NULL_CHARACTER must be employed; using NULL is not
    1141:    correct for character data!  Thus, NULL_CHARACTER can be
    1142:    used for the display and title input parameters.

    1144:    Concepts: OpenGL^drawing to

    1146: .seealso: PetscDrawFlush(), PetscDrawDestroy(), PetscDrawOpenX(), PetscDrawCreate()
    1147: @*/
    1148: PetscErrorCode  PetscDrawOpenGLUT(MPI_Comm comm,const char display[],const char title[],int x,int y,int w,int h,PetscDraw *draw)
    1149: {

    1153:   PetscDrawCreate(comm,display,title,x,y,w,h,draw);
    1154:   PetscDrawSetType(*draw,PETSC_DRAW_GLUT);
    1155:   return(0);
    1156: }

    1158: #elif defined(PETSC_HAVE_OPENGLES)

    1160: PetscErrorCode  PetscDrawOpenGLESRegisterGLKView(GLKView *view)
    1161: {
    1162:   PetscInt i;

    1165:   for (i=0; i<10; i++) {
    1166:     if (view == globalGLKView[i]) return(0);  /* already registered */
    1167:     if (!globalGLKView[i]) {
    1168:       globalGLKView[i] = view;
    1169:       return(0);
    1170:     }
    1171:   }
    1172:   SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Out of GLKView slots");
    1173:   return(0);
    1174: }

    1176: PETSC_EXTERN PetscErrorCode PetscDrawCreate_OpenGLES(PetscDraw draw)
    1177: {
    1178:   PetscDraw_OpenGL *win;
    1179:   PetscErrorCode   ierr;
    1180:   static PetscBool initialized = PETSC_FALSE;
    1181:   PetscInt         i;

    1184:   NSLog(@"Beginning PetscDrawCreate_OpenGLES()");

    1186:   PetscMemcpy(draw->ops,&DvOps,sizeof(DvOps));
    1187:   PetscNew(&win);
    1188:   PetscLogObjectMemory((PetscObject)draw,sizeof(PetscDraw_OpenGL));

    1190:   draw->data = win;
    1191:   win->view  = -1;
    1192:   for (i=0; i<10; i++) {
    1193:     if (!globalGLKViewUsed[i]) {
    1194:       win->view = i;
    1195:       win->w    = globalGLKView[win->view].frame.size.width;
    1196:       win->h    = globalGLKView[win->view].frame.size.height;
    1197:       [globalGLKView[win->view] bindDrawable];
    1198:       globalGLKViewUsed[i] = 1;
    1199:       break;
    1200:     }
    1201:   }
    1202:   if (win->view == -1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Requested more OpenGL ES windows then provided with PetscDrawOpenGLRegisterGLKView()");

    1204:   if (!initialized) {
    1205:     initialized = PETSC_TRUE;
    1206:     InitializeColors();
    1207:   }
    1208:   InitializeShader();

    1210:   PetscDrawClear(draw);
    1211:   NSLog(@"Ending PetscDrawCreate_OpenGLES()");
    1212:   return(0);
    1213: }

    1215: #endif