+ vp = brw_state_batch(brw, AUB_TRACE_CLIP_VP_STATE,
+ sizeof(*vp) * ctx->Const.MaxViewports, 32, &brw->clip.vp_offset);
+
+ for (unsigned i = 0; i < ctx->Const.MaxViewports; i++) {
+ /* According to the "Vertex X,Y Clamping and Quantization" section of the
+ * Strips and Fans documentation, objects must not have a screen-space
+ * extents of over 8192 pixels, or they may be mis-rasterized. The maximum
+ * screen space coordinates of a small object may larger, but we have no
+ * way to enforce the object size other than through clipping.
+ *
+ * If you're surprised that we set clip to -gbx to +gbx and it seems like
+ * we'll end up with 16384 wide, note that for a 8192-wide render target,
+ * we'll end up with a normal (-1, 1) clip volume that just covers the
+ * drawable.
+ */
+ const float maximum_post_clamp_delta = 8192;
+ float gbx = maximum_post_clamp_delta / ctx->ViewportArray[i].Width;
+ float gby = maximum_post_clamp_delta / ctx->ViewportArray[i].Height;