intel: Fallback to software if drawable size is > MaxRenderbufferSize

[mesa.git] / src / mesa / drivers / dri / intel / intel_buffers.c

diff --git a/src/mesa/drivers/dri/intel/intel_buffers.c b/src/mesa/drivers/dri/intel/intel_buffers.c
index df5c3fc1766f40cbb3487fea397db96bb1b79d0a..4b8ac364f7906656e2be0b254e730ed1667478cb 100644 (file)
--- a/src/mesa/drivers/dri/intel/intel_buffers.c
+++ b/src/mesa/drivers/dri/intel/intel_buffers.c
@@ -172,10 +172,15 @@ intel_draw_buffer(GLcontext * ctx, struct gl_framebuffer *fb)
       return;
    }
 
-   /*
-    * How many color buffers are we drawing into?
+   /* How many color buffers are we drawing into?
+    *
+    * If there are zero buffers or the buffer is too big, don't configure any
+    * regions for hardware drawing.  We'll fallback to software below.  Not
+    * having regions set makes some of the software fallback paths faster.
     */
-   if (fb->_NumColorDrawBuffers == 0) {
+   if ((fb->Width > ctx->Const.MaxRenderbufferSize)
+       || (fb->Height > ctx->Const.MaxRenderbufferSize)
+       || (fb->_NumColorDrawBuffers == 0)) {
       /* writing to 0  */
       colorRegions[0] = NULL;
       intel->constant_cliprect = GL_TRUE;
@@ -345,6 +350,23 @@ intelDrawBuffer(GLcontext * ctx, GLenum mode)
 static void
 intelReadBuffer(GLcontext * ctx, GLenum mode)
 {
+   if ((ctx->DrawBuffer != NULL) && (ctx->DrawBuffer->Name == 0)) {
+      struct intel_context *const intel = intel_context(ctx);
+      const GLboolean was_front_buffer_reading =
+       intel->is_front_buffer_reading;
+
+      intel->is_front_buffer_reading = (mode == GL_FRONT_LEFT)
+       || (mode == GL_FRONT);
+
+      /* If we weren't front-buffer reading before but we are now, make sure
+       * that the front-buffer has actually been allocated.
+       */
+      if (!was_front_buffer_reading && intel->is_front_buffer_reading) {
+        intel_update_renderbuffers(intel->driContext,
+                                   intel->driContext->driDrawablePriv);
+      }
+   }
+
    if (ctx->ReadBuffer == ctx->DrawBuffer) {
       /* This will update FBO completeness status.
        * A framebuffer will be incomplete if the GL_READ_BUFFER setting