st/mesa: don't expose ARB_color_buffer_float without driver support in GL core

Reviewed-by: Brian Paul <brianp@vmware.com>

diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 11db9d3f318f1687c9a6e9653a0697f1fda89f7e..2d8b9efec4ebd4dc2f7a393cf71c492550b2445e 100644 (file)
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -629,6 +629,7 @@ void st_init_extensions(struct st_context *st)
       ctx->Const.PrimitiveRestartInSoftware = GL_TRUE;
    }
 
+   /* ARB_color_buffer_float. */
    if (screen->get_param(screen, PIPE_CAP_VERTEX_COLOR_UNCLAMPED)) {
       ctx->Extensions.ARB_color_buffer_float = GL_TRUE;
 
@@ -639,6 +640,16 @@ void st_init_extensions(struct st_context *st)
       if (!screen->get_param(screen, PIPE_CAP_FRAGMENT_COLOR_CLAMPED)) {
          st->clamp_frag_color_in_shader = TRUE;
       }
+
+      /* For drivers which cannot do color clamping, it's better to just
+       * disable ARB_color_buffer_float in the core profile, because
+       * the clamping is deprecated there anyway. */
+      if (ctx->API == API_OPENGL_CORE &&
+          (st->clamp_frag_color_in_shader || st->clamp_vert_color_in_shader)) {
+         st->clamp_vert_color_in_shader = GL_FALSE;
+         st->clamp_frag_color_in_shader = GL_FALSE;
+         ctx->Extensions.ARB_color_buffer_float = GL_FALSE;
+      }
    }
 
    if (screen->fence_finish) {