/* * $Id: glcanvas.c,v 0.89 1999/07/17 03:17:52 zhao Beta $ *. * This file is part of XForms package * Copyright (c) 1996-2000 T.C. Zhao and Mark Overmars * All rights reserved. *. * * A sample implementation of OpenGL/Mesa canvas class. * * For typical objects, ob->spec is the place for the * object specific info. For OpenGL canvas, however, the * ob->spec is already used by the generic canvas. We use * ob->c_vdata to hang the OpenGL specific stuff. * * See ../DEMOS/gl.c for an example use of glcanvas. * See ../DEMOS/glwin.c for an example use of fl_glwinopen * */ #if defined(F_ID) || defined(DEBUG) char *fl_id_gl = "$Id: glcanvas.c,v 0.89 1999/07/17 03:17:52 zhao Beta $"; #endif #include "GL/glx.h" #include "GL/gl.h" #include "forms.h" #include #define MAXATTRIB 34 typedef struct { XVisualInfo *xvinfo; GLXContext context; int direct; int glconfig[MAXATTRIB]; } CSPEC; /* * Default GL canvas configuration. The user can modify this default * using fl_set_glcanvas_defaults(const int *config) or * fl_set_glcanvas_attributes(FL_OBJECT *, const int *config) * */ static int glconfig[MAXATTRIB] = { GLX_RGBA, GLX_DEPTH_SIZE, 1, GLX_RED_SIZE, 1, GLX_GREEN_SIZE, 1, GLX_BLUE_SIZE, 1, GLX_DOUBLEBUFFER, None }; #define GLPROP(ob) ((CSPEC *)(ob->c_vdata)) #define ISGLC(ob) (ob && ob->objclass == FL_GLCANVAS) static int glx_init(FL_OBJECT *), glx_activate(FL_OBJECT *); static int glx_cleanup(FL_OBJECT *); static void copy_attributes(int *, const int *); /* Add a GL canvas to the form */ FL_OBJECT * fl_add_glcanvas(int type, FL_Coord x, FL_Coord y, FL_Coord w, FL_Coord h, const char *label) { FL_OBJECT *ob = fl_create_glcanvas(type, x, y, w, h, label); fl_add_object(fl_current_form, ob); return ob; } /* modify the global defaults */ void fl_set_glcanvas_defaults(const int *config) { copy_attributes(glconfig, config); } void fl_get_glcanvas_defaults(int config[]) { copy_attributes(config, glconfig); } /* modify the default configuration of a particular canvas */ void fl_set_glcanvas_attributes(FL_OBJECT * ob, const int *config) { if (!ISGLC(ob)) fprintf(stderr, "object %s is not glcanvas\n", ob ? ob->label : "null"); copy_attributes(GLPROP(ob)->glconfig, config); if (ob->visible) { fl_hide_object(ob); fl_show_object(ob); } } void fl_get_glcanvas_attributes(FL_OBJECT * ob, int *attributes) { copy_attributes(attributes, GLPROP(ob)->glconfig); } void fl_set_glcanvas_direct(FL_OBJECT * ob, int direct) { if (direct != GLPROP(ob)->direct) { GLPROP(ob)->direct = direct ? GL_TRUE : GL_FALSE; if (ob->visible) { fl_hide_object(ob); fl_show_object(ob); } } } GLXContext fl_get_glcanvas_context(FL_OBJECT * ob) { return GLPROP(ob)->context; } XVisualInfo * fl_get_glcanvas_xvisualinfo(FL_OBJECT * ob) { return GLPROP(ob)->xvinfo; } void fl_activate_glcanvas(FL_OBJECT * ob) { if (FL_ObjWin(ob)) glx_activate(ob); } /* Interface routines */ FL_OBJECT * fl_create_glcanvas(int type, FL_Coord x, FL_Coord y, FL_Coord w, FL_Coord h, const char *label) { FL_OBJECT *ob = fl_create_canvas(type, x, y, w, h, label); ob->objclass = FL_GLCANVAS; fl_modify_canvas_prop(ob, glx_init, glx_activate, glx_cleanup); /* initialize glcanvas specific stuff */ ob->c_vdata = fl_calloc(1, sizeof(CSPEC)); memcpy(GLPROP(ob)->glconfig, glconfig, sizeof(glconfig)); GLPROP(ob)->direct = GL_TRUE; return ob; } /* Initialize the OpenGL stuff before window creation */ static int glx_init(FL_OBJECT * ob) { XVisualInfo *vi; GLXContext context; /* query for openGL capabilities */ if (!glXQueryExtension(fl_display, 0, 0)) { fprintf(stderr, "GLCanvas: OpenGL not supported\n"); return -1; } if (!(vi = glXChooseVisual(fl_display, fl_screen, GLPROP(ob)->glconfig))) { /* if can't get a visual, quit */ fprintf(stderr, "GLCanvas: Can't get visual\n"); return -1; } /* change canvas defaults */ fl_set_canvas_visual(ob, vi->visual); fl_set_canvas_depth(ob, vi->depth); fl_set_canvas_colormap(ob, fl_create_colormap(vi, 1)); context = glXCreateContext(fl_display, vi, None, GLPROP(ob)->direct); if (!context) { fprintf(stderr, "Can't create GLX context!\n"); return -1; } /* under some conditions, the parent of the gl canvas might go away, leaving the old context and vi hanging. */ glx_cleanup(ob); GLPROP(ob)->context = context; GLPROP(ob)->xvinfo = vi; return 0; } /* This routine is called after a valid window is created. It simply * binds the OpenGL context to the canvas window */ static int glx_activate(FL_OBJECT * ob) { glXMakeCurrent(fl_display, FL_ObjWin(ob), GLPROP(ob)->context); return 0; } /* * cleanup is called before destroying the window. Might be called * more than once */ static int glx_cleanup(FL_OBJECT * ob) { if (GLPROP(ob)->context) { glXDestroyContext(fl_display, GLPROP(ob)->context); XFree(GLPROP(ob)->xvinfo); GLPROP(ob)->context = 0; GLPROP(ob)->xvinfo = 0; } return 0; } static void copy_attributes(int *dest, const int *src) { while (*src != None) *dest++ = *src++; *dest = None; } /************************************************************* * Open a top-level OpenGL window. * * fl_winset won't work for switching OpenGL windows. * Use glXMakeCurrent ************************************************************/ Window fl_glwincreate(int *config, GLXContext * context, int w, int h) { XVisualInfo *xvi; XSetWindowAttributes xswa; unsigned mask; Window win; if (!glXQueryExtension(fl_display, 0, 0)) return 0; if (!(xvi = glXChooseVisual(fl_display, fl_screen, config ? config : glconfig))) return 0; *context = glXCreateContext(fl_display, xvi, None, GL_TRUE); xswa.colormap = fl_create_colormap(xvi, 1); xswa.border_pixel = 0; mask = CWColormap | CWBorderPixel; xswa.event_mask = ExposureMask; mask |= CWEventMask; win = XCreateWindow(fl_display, RootWindow(fl_display, fl_screen), 0, 0, w, h, 0, xvi->depth, InputOutput, xvi->visual, mask, &xswa); if (win) glXMakeCurrent(fl_display, win, *context); return win; } Window fl_glwinopen(int *config, GLXContext * context, int w, int h) { Window win; if ((win = fl_glwincreate(config, context, w, h))) fl_winshow(win); return win; }