static support_mode is_supported(const char *extensions, const array<long, 2> &version, const char *name, long major, long minor, long major_es, long minor_es)
{
#if DXX_USE_OGLES
static_cast<void>(major);
static_cast<void>(minor);
if ( (major_es > 0) && ((version[0] > major_es) || (version[0] == major_es && version[1] >= minor_es)) )
return SUPPORT_CORE;
#else
static_cast<void>(major_es);
static_cast<void>(minor_es);
if ( (major > 0) && ((version[0] > major) || (version[0] == major && version[1] >= minor)) )
return SUPPORT_CORE;
#endif
if (is_ext_supported(extensions, name))
return SUPPORT_EXT;
return NO_SUPPORT;
}
int
main()
{
GLXFBConfig fbconfig;
Vec2u screen_dim { 1200, 900 };
// create window
{
int buffer_attribs[] = {
GLX_X_RENDERABLE , True,
GLX_DRAWABLE_TYPE , GLX_WINDOW_BIT,
GLX_RENDER_TYPE , GLX_RGBA_BIT,
GLX_X_VISUAL_TYPE , GLX_TRUE_COLOR,
GLX_RED_SIZE , 8,
GLX_GREEN_SIZE , 8,
GLX_BLUE_SIZE , 8,
GLX_ALPHA_SIZE , 8,
GLX_DEPTH_SIZE , 24,
GLX_STENCIL_SIZE , 8,
GLX_DOUBLEBUFFER , True,
//GLX_SAMPLE_BUFFERS , 1,
//GLX_SAMPLES , 4,
None
};
g_pctx.display = XOpenDisplay(NULL);
if (!g_pctx.display)
zabort("failed to create display");
int xscreen = XDefaultScreen(g_pctx.display), num_fbconfigs;
GLXFBConfig *fbconfigs = glXChooseFBConfig(g_pctx.display, xscreen, buffer_attribs, &num_fbconfigs);
if (!fbconfigs)
zabort("Failed to retrieve frame buffer configs");
int best_fbc = -1, best_num_samp = -1;
for (int i = 0; i < num_fbconfigs; ++i) {
XVisualInfo *visual = glXGetVisualFromFBConfig(g_pctx.display, fbconfigs[i]);
if (visual) {
int samp_buf, samples;
glXGetFBConfigAttrib(g_pctx.display, fbconfigs[i], GLX_SAMPLE_BUFFERS, &samp_buf);
glXGetFBConfigAttrib(g_pctx.display, fbconfigs[i], GLX_SAMPLES, &samples);
if (best_fbc < 0 || (samp_buf && samples > best_num_samp))
best_fbc = i, best_num_samp = samples;
//if (worst_fbc < 0 || !samp_buf || samples < worst_num_samp)
//worst_fbc = i, worst_num_samp = samples;
}
XFree(visual);
}
if (best_fbc < 0)
zabort("failed to get a frame buffer");
fbconfig = fbconfigs[0];
XFree(fbconfigs);
XVisualInfo *visual = glXGetVisualFromFBConfig(g_pctx.display, fbconfig);
Window root = DefaultRootWindow(g_pctx.display);
XSetWindowAttributes win_attribs;
win_attribs.colormap = XCreateColormap(g_pctx.display, root, visual->visual, AllocNone);
win_attribs.background_pixmap = None;
win_attribs.border_pixmap = None;
win_attribs.border_pixel = 0;
win_attribs.event_mask =
StructureNotifyMask |
FocusChangeMask |
EnterWindowMask |
LeaveWindowMask |
ExposureMask |
ButtonPressMask |
ButtonReleaseMask |
OwnerGrabButtonMask |
KeyPressMask |
KeyReleaseMask;
int win_attribs_mask =
CWBackPixmap|
CWColormap|
CWBorderPixel|
CWEventMask;
assert(visual->c_class == TrueColor);
g_pctx.window = XCreateWindow(g_pctx.display, root, 0, 0, screen_dim.x, screen_dim.y, 0, visual->depth, InputOutput, visual->visual, win_attribs_mask, &win_attribs);
if (!g_pctx.window)
zabort("Failed to create a window.\n");
XFree(visual);
XStoreName(g_pctx.display, g_pctx.window, "cge");
XMapWindow(g_pctx.display, g_pctx.window);
if ((g_pctx.wm_delete_window = XInternAtom(g_pctx.display, "WM_DELETE_WINDOW", 1)))
XSetWMProtocols(g_pctx.display, g_pctx.window, &g_pctx.wm_delete_window, 1);
else
zerror("Unable to register WM_DELETE_WINDOW atom");
}
// Create OpenGL context.
{
int major_ver, minor_ver;
if (!glXQueryVersion(g_pctx.display, &major_ver, &minor_ver))
zabort("Unable to query GLX version");
if ((major_ver == 1 && minor_ver < 3) || major_ver < 1)
zabort("GLX version is too old");
// Install a new error handler so that the program doesn't just exit if we fail to get a 3.1 context.
// Note this error handler is global. All display connections in all threads of a process use the same error handler.
ctx_error_occured = false;
int (*old_handler)(Display*, XErrorEvent*) = XSetErrorHandler(&ctx_error_handler);
const char *gl_exts = glXQueryExtensionsString(g_pctx.display, XDefaultScreen(g_pctx.display));
if (!is_ext_supported(gl_exts, "GLX_ARB_create_context"))
zabort("OpenGL does not support glXCreateContextAttribsARB extension");
int context_attribs[] = {
GLX_CONTEXT_MAJOR_VERSION_ARB, 3,
GLX_CONTEXT_MINOR_VERSION_ARB, 1,
//GLX_CONTEXT_FLAGS_ARB , GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
None
};
typedef GLXContext (*glXCreateContextAttribsARBProc)(Display*, GLXFBConfig, GLXContext, Bool, const int*);
glXCreateContextAttribsARBProc glXCreateContextAttribsARB = NULL;
glXCreateContextAttribsARB = (glXCreateContextAttribsARBProc)glXGetProcAddressARB((const GLubyte *)"glXCreateContextAttribsARB");
if (!glXCreateContextAttribsARB)
zabort("Could not load glXCreateContextAttribsARB");
g_pctx.gl_context = NULL;
g_pctx.gl_context = glXCreateContextAttribsARB(g_pctx.display, fbconfig, 0, True, context_attribs);
XSync(g_pctx.display, False);
if (ctx_error_occured || !g_pctx.gl_context)
zabort("Failed to create OpenGL context");
XSetErrorHandler(old_handler);
glXMakeCurrent(g_pctx.display, g_pctx.window, g_pctx.gl_context);
}
// Load OpenGL functions.
#define LOADPROC
#include "glprocs.h"
#undef LOADPROC
main_loop(screen_dim);
platform_exit();
return 0;
}