+/* gltest - small OpenGL tearing test program
+ * Copyright (C) 2012-2013 Ralf Jung <post@ralfj.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
#include "glxbackend.h"
+#include "glutil.h"
#include <stdio.h>
#include <assert.h>
+#include <stdlib.h>
#include <GL/glxext.h>
#include <string>
-/* attributes for a double buffered visual in RGBA format with at least
-* 4 bits per color */
-static int attrList[] =
-{
- GLX_RGBA, GLX_DOUBLEBUFFER,
- GLX_RED_SIZE, 4,
- GLX_GREEN_SIZE, 4,
+#if !defined(CON_GL1) && !defined(CON_GL3)
+#error "Valid GL contexts for GLX are: GL1, GL3"
+#endif
+
+// attributes for a double buffered framebuffer in RGBA format with at least 4 bits per color
+static int configAttribs[] =
+{
+ GLX_RENDER_TYPE, GLX_RGBA_BIT,
+ GLX_DOUBLEBUFFER, True,
+ GLX_RED_SIZE, 4,
+ GLX_GREEN_SIZE, 4,
GLX_BLUE_SIZE, 4,
- None
+ None
};
+#ifdef CON_GL3
+// attributes for a GL3 context
+static int contextAttribs[] =
+{
+ GLX_CONTEXT_MAJOR_VERSION_ARB, 3,
+ GLX_CONTEXT_MINOR_VERSION_ARB, 0,
+ GLX_CONTEXT_FLAGS_ARB, GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
+ None
+};
+#endif
+
VisualID GLXBackend::initialize(Display *display)
{
if (this->display == NULL) { // this implies that the context is also unitialized
// debugging: show version information
int glxMajor, glxMinor;
glXQueryVersion(display, &glxMajor, &glxMinor);
- printf("Using GLX version %d.%d\n", glxMajor, glxMinor);
- // check for swap control functions
- const char *extensions = glXQueryExtensionsString(display, DefaultScreen(display));
- if (std::string(extensions).find("GLX_MESA_swap_control") != std::string::npos) {
- funSwapIntervalMesa = (PFNGLXSWAPINTERVALMESAPROC)glXGetProcAddress((const GLubyte*)"glXSwapIntervalMESA");
- if (funSwapIntervalMesa) printf("glXSwapIntervalMESA is present\n");
- }
- else {
- funSwapIntervalMesa = 0;
+ printf("Using GLX version: %d.%d\n", glxMajor, glxMinor);
+ if (glxMajor < 1 || (glxMajor == 1 && glxMinor < 3)) {
+ // glXChooseFBConfig and glXCreateNewContext require GLX 1.3
+ fprintf(stderr, "Need at least GLX 1.3 to function properly\n");
+ exit(1);
}
- if (std::string(extensions).find("GLX_EXT_swap_control") != std::string::npos) {
- funSwapIntervalExt = (PFNGLXSWAPINTERVALEXTPROC)glXGetProcAddress((const GLubyte*)"glXSwapIntervalEXT");
- if (funSwapIntervalExt) printf("glXSwapIntervalEXT is present\n");
+ // check for extension-based functions
+ funSwapIntervalMesa = (PFNGLXSWAPINTERVALMESAPROC)resolveGLXFunction("GLX_MESA_swap_control", "glXSwapIntervalMESA");
+ funSwapIntervalExt = (PFNGLXSWAPINTERVALEXTPROC)resolveGLXFunction("GLX_EXT_swap_control", "glXSwapIntervalEXT");
+ funCreateContextAttribsARB = (PFNGLXCREATECONTEXTATTRIBSARBPROC)resolveGLXFunction("GLX_ARB_create_context", "glXCreateContextAttribsARB");
+ // get the first usable framebuffer configuration
+ int count = 0;
+ GLXFBConfig *configs = glXChooseFBConfig(display, DefaultScreen(display), configAttribs, &count);
+ if (count < 1) {
+ fprintf(stderr, "Failed to choose framebuffer configuration\n");
+ exit(1);
}
- else {
- funSwapIntervalExt = 0;
- }
- // get the visual
- vi = glXChooseVisual(display, DefaultScreen(display), attrList);
+ config = configs[0];
+ XFree(configs);
}
- return vi->visualid;
+ // return visual ID
+ XVisualInfo *vi = glXGetVisualFromFBConfig(display, config);
+ VisualID visualid = vi->visualid;
+ XFree(vi);
+ return visualid;
+}
+
+bool GLXBackend::haveGLXExtension(const std::string &name)
+{
+ assert(display != NULL);
+ std::string extensions = glXQueryExtensionsString(display, DefaultScreen(display));
+ return (std::string(" "+extensions+" ").find(" "+name+" ") != std::string::npos);
+}
+
+T_proc GLXBackend::resolveGLXFunction(const char *extension, const char *function)
+{
+ if (!haveGLXExtension(extension)) return NULL;
+ T_proc f = glXGetProcAddress((const GLubyte*)function);
+ if (f)
+ printf("%s is supported, using it for %s\n", extension, function);
+ return f;
}
void GLXBackend::createContext(Window window)
assert(display != NULL && context == None);
this->window = window;
// create context with that window
- context = glXCreateContext(display, vi, 0, GL_TRUE);
+#ifdef CON_GL1
+ context = glXCreateNewContext(display, config, GLX_RGBA_TYPE, NULL, GL_TRUE);
+#else
+ if (!funCreateContextAttribsARB) {
+ fprintf(stderr, "Cannot create GL3 context: GLX_ARB_create_context not supported\n");
+ exit(1);
+ }
+ context = funCreateContextAttribsARB(display, config, NULL, GL_TRUE, contextAttribs);
+#endif
+ if (!context) {
+ fprintf(stderr, "Error creating context\n");
+ exit(1);
+ }
glXMakeCurrent(display, window, context);
assert(glXIsDirect(display, context));
+ printf("Using GL version: %s\n", glGetString(GL_VERSION));
+ // initialise GL utilities
+ resolveFunctionPointers((T_glGetProcAddress)glXGetProcAddress);
}
GLXBackend::~GLXBackend()
glXMakeCurrent(display, None, NULL);
glXDestroyContext(display, context);
}
- XFree(vi);
}
}
void GLXBackend::setSwapInterval(int i) const
{
assert(context != None);
+ // check if swap interval value is supported
+ if (i < 0) {
+ fprintf(stderr, "Cannot set swap interval to %d, must not be negative\n", i);
+ exit(1);
+ }
+ // set it
if (funSwapIntervalExt)
funSwapIntervalExt(display, window, i);
else if (funSwapIntervalMesa)
funSwapIntervalMesa(i);
- else
- assert(false && "At least one of glXSwapIntervalMESA, glXSwapIntervalEXT must be provided by the system");
+ else {
+ fprintf(stderr, "At least one of GLX_EXT_swap_control, GLX_MESA_swap_control must be supported by the system\n");
+ abort();
+ }
}