render/opengl/linux/egl: pick config in init; pass to context; bind pbuffer

src/render/opengl/linux/egl/render_opengl_linux_egl.c

@@ -51,7 +51,63 @@ r_ogl_os_init(CmdLine *cmdln)
     wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't initialize EGL API to OpenGL."));
     abort_self(1);
   }
-  
+
+  //- choose EGL config, extract matching X11 visual/colormap, publish to os layer
+  {
+    EGLint config_filter[] =
+    {
+      EGL_SURFACE_TYPE,      EGL_WINDOW_BIT|EGL_PBUFFER_BIT,
+      EGL_CONFORMANT,        EGL_OPENGL_BIT,
+      EGL_RENDERABLE_TYPE,   EGL_OPENGL_BIT,
+      EGL_COLOR_BUFFER_TYPE, EGL_RGB_BUFFER,
+      EGL_RED_SIZE,          8,
+      EGL_GREEN_SIZE,        8,
+      EGL_BLUE_SIZE,         8,
+      EGL_DEPTH_SIZE,        24,
+      EGL_STENCIL_SIZE,      8,
+      EGL_NONE,
+    };
+    EGLConfig configs[256] = {0};
+    EGLint configs_count = 0;
+    if(!eglChooseConfig(r_ogl_lnx_state->display, config_filter, configs, ArrayCount(configs), &configs_count) || configs_count == 0)
+    {
+      wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't choose EGL configuration."));
+      abort_self(1);
+    }
+    int screen = DefaultScreen(lnx_wm_state->display);
+    XVisualInfo vi_template = {0};
+    XVisualInfo *vi = 0;
+    int vi_count = 0;
+    for(EGLint idx = 0; idx < configs_count && vi == 0; idx += 1)
+    {
+      EGLint native_visual_id = 0;
+      if(!eglGetConfigAttrib(r_ogl_lnx_state->display, configs[idx], EGL_NATIVE_VISUAL_ID, &native_visual_id) || native_visual_id == 0)
+      {
+        continue;
+      }
+      vi_template.visualid = native_visual_id;
+      vi_template.screen = screen;
+      vi = XGetVisualInfo(lnx_wm_state->display, VisualIDMask|VisualScreenMask, &vi_template, &vi_count);
+      if(vi != 0 && vi_count > 0)
+      {
+        r_ogl_lnx_state->config = configs[idx];
+        break;
+      }
+      if(vi != 0) { XFree(vi); vi = 0; }
+    }
+    if(vi == 0 || r_ogl_lnx_state->config == 0)
+    {
+      wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't find an EGL config with a matching X11 visual."));
+      abort_self(1);
+    }
+    lnx_wm_state->window_visual = vi->visual;
+    lnx_wm_state->window_depth = vi->depth;
+    lnx_wm_state->window_colormap = XCreateColormap(lnx_wm_state->display,
+                                                        XRootWindow(lnx_wm_state->display, vi->screen),
+                                                        vi->visual, AllocNone);
+    XFree(vi);
+  }
+
   //- rjf: construct context
   {
     B32 debug_mode = cmd_line_has_flag(cmdln, str8_lit("opengl_debug"));
@@ -66,16 +122,23 @@ r_ogl_os_init(CmdLine *cmdln)
       debug_mode ? EGL_CONTEXT_OPENGL_DEBUG : EGL_NONE, EGL_TRUE,
       EGL_NONE,
     };
-    r_ogl_lnx_state->context = eglCreateContext(r_ogl_lnx_state->display, 0, EGL_NO_CONTEXT, options);
+    r_ogl_lnx_state->context = eglCreateContext(r_ogl_lnx_state->display, r_ogl_lnx_state->config, EGL_NO_CONTEXT, options);
     if(r_ogl_lnx_state->context == EGL_NO_CONTEXT)
     {
       wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't create OpenGL context with EGL."));
       abort_self(1);
     }
   }
-  
+
-  eglMakeCurrent(r_ogl_lnx_state->display, 0, 0, r_ogl_lnx_state->context);
+  //- bind context to 1x1 pbuffer so GL calls work before any window exists
-  glDrawBuffer(GL_BACK);
+  {
+    EGLint pbuffer_attribs[] = { EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE };
+    EGLSurface init_surface = eglCreatePbufferSurface(r_ogl_lnx_state->display, r_ogl_lnx_state->config, pbuffer_attribs);
+    if(init_surface == EGL_NO_SURFACE || !eglMakeCurrent(r_ogl_lnx_state->display, init_surface, init_surface, r_ogl_lnx_state->context))
+    {
+      eglMakeCurrent(r_ogl_lnx_state->display, EGL_NO_SURFACE, EGL_NO_SURFACE, r_ogl_lnx_state->context);
+    }
+  }
 }
 
 internal R_Handle
@@ -97,60 +160,11 @@ r_ogl_os_window_equip(WM_Window window)
       EGL_GL_COLORSPACE, EGL_GL_COLORSPACE_SRGB,
       EGL_NONE,
     };
-    if(r_ogl_lnx_state->config == 0)
+    w->surface = eglCreateWindowSurface(r_ogl_lnx_state->display, r_ogl_lnx_state->config, window_os->window, surface_options);
+    if(w->surface == EGL_NO_SURFACE)
     {
-      //- rjf: get all EGL configs
+      EGLint surface_options_linear[] = { EGL_NONE };
-      EGLConfig configs[256] = {0};
+      w->surface = eglCreateWindowSurface(r_ogl_lnx_state->display, r_ogl_lnx_state->config, window_os->window, surface_options_linear);
-      EGLint configs_count = 0;
-      {
-        EGLint options[] =
-        {
-          EGL_SURFACE_TYPE,      EGL_WINDOW_BIT,
-          EGL_CONFORMANT,        EGL_OPENGL_BIT,
-          EGL_RENDERABLE_TYPE,   EGL_OPENGL_BIT,
-          EGL_COLOR_BUFFER_TYPE, EGL_RGB_BUFFER,
-          
-          EGL_RED_SIZE,      8,
-          EGL_GREEN_SIZE,    8,
-          EGL_BLUE_SIZE,     8,
-          EGL_DEPTH_SIZE,   24,
-          EGL_STENCIL_SIZE,  8,
-          
-          EGL_NONE,
-        };
-        if(!eglChooseConfig(r_ogl_lnx_state->display, options, configs, ArrayCount(configs), &configs_count) || configs_count == 0)
-        {
-          wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't choose EGL configuration."));
-          abort_self(1);
-        }
-      }
-      
-      //- rjf: actually choose the egl config
-      {
-        EGLint config_options[] =
-        {
-          EGL_GL_COLORSPACE, EGL_GL_COLORSPACE_SRGB,
-          EGL_NONE,
-        };
-        for(U32 idx = 0; idx < configs_count; idx += 1)
-        {
-          w->surface = eglCreateWindowSurface(r_ogl_lnx_state->display, configs[idx], window_os->window, config_options);
-          if(w->surface != EGL_NO_SURFACE)
-          {
-            r_ogl_lnx_state->config = configs[idx];
-            break;
-          }
-        }
-        if(r_ogl_lnx_state->config == 0)
-        {
-          wm_graphical_message(1, str8_lit("Fatal Error"), str8_lit("Couldn't find a suitable EGL configuration."));
-          abort_self(1);
-        }
-      }
-    }
-    else
-    {
-      w->surface = eglCreateWindowSurface(r_ogl_lnx_state->display, r_ogl_lnx_state->config, window_os->window, surface_options);
     }
     if(w->surface == EGL_NO_SURFACE)
     {

src/render/opengl/linux/egl/render_opengl_linux_egl.h

@@ -7,6 +7,7 @@
 #define glTexImage3D glTexImage3D__static
 #define glTexSubImage3D glTexSubImage3D__static
 #define glActiveTexture glActiveTexture__static
+#include <X11/Xutil.h>
 #include <GL/gl.h>
 #include <EGL/egl.h>
 #undef glTexImage3D