diff options
Diffstat (limited to 'samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c')
| -rw-r--r-- | samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c | 90 |
1 files changed, 86 insertions, 4 deletions
diff --git a/samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c b/samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c index 643c0ca..7aae5a8 100644 --- a/samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c +++ b/samples/OpenGL/x11argb_opengl_glsl/x11argb_opengl_glsl.c @@ -24,12 +24,17 @@ ------------------------------------------------------------------------*/ +#define _GNU_SOURCE + #include <stdlib.h> #include <stdio.h> #include <string.h> #include <math.h> #include <sys/time.h> +#include <sys/types.h> +#include <time.h> + #include <GL/glew.h> #include <GL/glx.h> #include <X11/Xatom.h> @@ -62,7 +67,7 @@ static const GLchar *fragment_shader_source = " vec2 mod_texcoord = gl_TexCoord[0].st*vec2(1., 2.) + vec2(0, -0.5 + 0.5*sin(T + 1.5*ts*pi));\n" " if( mod_texcoord.t < 0. || mod_texcoord.t > 1. ) { discard; }\n" " gl_FragColor = -texture2D(texCMYK, mod_texcoord) + texture2D(texRGB, gl_TexCoord[0].st);\n" -" gl_FragColor.a = -0.5;\n" +" gl_FragColor.a = 1.;\n" "}\n\0"; GLuint shaderFragment = 0; @@ -130,6 +135,37 @@ static void fatalError(const char *why) exit(0x666); } +static int isExtensionSupported(const char *extList, const char *extension) +{ + + const char *start; + const char *where, *terminator; + + /* Extension names should not have spaces. */ + where = strchr(extension, ' '); + if ( where || *extension == '\0' ) + return 0; + + /* It takes a bit of care to be fool-proof about parsing the + OpenGL extensions string. Don't be fooled by sub-strings, + etc. */ + for ( start = extList; ; ) { + where = strstr( start, extension ); + + if ( !where ) + break; + + terminator = where + strlen( extension ); + + if ( where == start || *(where - 1) == ' ' ) + if ( *terminator == ' ' || *terminator == '\0' ) + return 1; + + start = terminator; + } + return 0; +} + static int Xscreen; static Atom del_atom; static Colormap cmap; @@ -304,6 +340,12 @@ static void createTheWindow() } } +static int ctxErrorHandler( Display *dpy, XErrorEvent *ev ) +{ + fputs("Error at context creation", stderr); + return 0; +} + static void createTheRenderContext() { int dummy; @@ -311,9 +353,46 @@ static void createTheRenderContext() fatalError("OpenGL not supported by X server\n"); } - render_context = glXCreateNewContext(Xdisplay, fbconfig, GLX_RGBA_TYPE, 0, True); - if (!render_context) { - fatalError("Failed to create a GL context\n"); +#if USE_GLX_CREATE_CONTEXT_ATTRIB + #define GLX_CONTEXT_MAJOR_VERSION_ARB 0x2091 + #define GLX_CONTEXT_MINOR_VERSION_ARB 0x2092 + render_context = NULL; + if( isExtensionSupported( glXQueryExtensionsString(Xdisplay, DefaultScreen(Xdisplay)), "GLX_ARB_create_context" ) ) { + typedef GLXContext (*glXCreateContextAttribsARBProc)(Display*, GLXFBConfig, GLXContext, Bool, const int*); + glXCreateContextAttribsARBProc glXCreateContextAttribsARB = (glXCreateContextAttribsARBProc)glXGetProcAddressARB( (const GLubyte *) "glXCreateContextAttribsARB" ); + if( glXCreateContextAttribsARB ) { + int context_attribs[] = + { + GLX_CONTEXT_MAJOR_VERSION_ARB, 3, + GLX_CONTEXT_MINOR_VERSION_ARB, 0, + //GLX_CONTEXT_FLAGS_ARB , GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB, + None + }; + + int (*oldHandler)(Display*, XErrorEvent*) = XSetErrorHandler(&ctxErrorHandler); + + render_context = glXCreateContextAttribsARB( Xdisplay, fbconfig, 0, True, context_attribs ); + + XSync( Xdisplay, False ); + XSetErrorHandler( oldHandler ); + + fputs("glXCreateContextAttribsARB failed", stderr); + } else { + fputs("glXCreateContextAttribsARB could not be retrieved", stderr); + } + } else { + fputs("glXCreateContextAttribsARB not supported", stderr); + } + + if(!render_context) + { +#else + { +#endif + render_context = glXCreateNewContext(Xdisplay, fbconfig, GLX_RGBA_TYPE, 0, True); + if (!render_context) { + fatalError("Failed to create a GL context\n"); + } } if (!glXMakeContextCurrent(Xdisplay, glX_window_handle, glX_window_handle, render_context)) { @@ -497,7 +576,10 @@ static void redrawTheWindow(double T) draw_cube(); popModelview(); + struct timespec Ta, Tb; + glXSwapBuffers(Xdisplay, glX_window_handle); + glXWaitGL(); } static double getftime(void) { |