[Mesa-dev] [PATCH 28/35] i965: Port gen6+ 3DSTATE_SCISSOR_STATE_POINTERS to use genxml.

[Rafael Antognolli]

Emit 3DSTATE_SCISSOR_STATE_POINTERS using brw_batch_emit, and pack the
scissor states using GENX(SCISSOR_RECT_pack), generated from genxml.

Signed-off-by: Rafael Antognolli <rafael.antognolli at intel.com>
---
 src/mesa/drivers/dri/i965/brw_state.h         |  1 +-
 src/mesa/drivers/dri/i965/genX_state_upload.c | 87 +++++++++++++++++++-
 2 files changed, 84 insertions(+), 4 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_state.h b/src/mesa/drivers/dri/i965/brw_state.h
index 66255ea..ac4f151 100644
--- a/src/mesa/drivers/dri/i965/brw_state.h
+++ b/src/mesa/drivers/dri/i965/brw_state.h
@@ -114,7 +114,6 @@ extern const struct brw_tracked_state gen6_gs_binding_table;
 extern const struct brw_tracked_state gen6_multisample_state;
 extern const struct brw_tracked_state gen6_renderbuffer_surfaces;
 extern const struct brw_tracked_state gen6_sampler_state;
-extern const struct brw_tracked_state gen6_scissor_state;
 extern const struct brw_tracked_state gen6_sol_surface;
 extern const struct brw_tracked_state gen6_sf_vp;
 extern const struct brw_tracked_state gen6_urb;
diff --git a/src/mesa/drivers/dri/i965/genX_state_upload.c b/src/mesa/drivers/dri/i965/genX_state_upload.c
index c3dcbc3..aa7aaac 100644
--- a/src/mesa/drivers/dri/i965/genX_state_upload.c
+++ b/src/mesa/drivers/dri/i965/genX_state_upload.c
@@ -2665,6 +2665,87 @@ static const struct brw_tracked_state genX(te_state) = {
 };
 #endif
 
+static void
+genX(upload_scissor_state)(struct brw_context *brw)
+{
+   struct gl_context *ctx = &brw->ctx;
+   const bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
+   struct GENX(SCISSOR_RECT) scissor;
+   uint32_t scissor_state_offset;
+   const unsigned int fb_width= _mesa_geometric_width(ctx->DrawBuffer);
+   const unsigned int fb_height = _mesa_geometric_height(ctx->DrawBuffer);
+   uint32_t *scissor_map;
+
+   /* BRW_NEW_VIEWPORT_COUNT */
+   const unsigned viewport_count = brw->clip.viewport_count;
+
+   scissor_map = brw_state_batch(
+      brw, GENX(SCISSOR_RECT_length) * sizeof(uint32_t) * viewport_count,
+      32, &scissor_state_offset);
+
+   /* _NEW_SCISSOR | _NEW_BUFFERS | _NEW_VIEWPORT */
+
+   /* The scissor only needs to handle the intersection of drawable and
+    * scissor rect.  Clipping to the boundaries of static shared buffers
+    * for front/back/depth is covered by looping over cliprects in brw_draw.c.
+    *
+    * Note that the hardware's coordinates are inclusive, while Mesa's min is
+    * inclusive but max is exclusive.
+    */
+   for (unsigned i = 0; i < viewport_count; i++) {
+      int bbox[4];
+
+      bbox[0] = MAX2(ctx->ViewportArray[i].X, 0);
+      bbox[1] = MIN2(bbox[0] + ctx->ViewportArray[i].Width, fb_width);
+      bbox[2] = MAX2(ctx->ViewportArray[i].Y, 0);
+      bbox[3] = MIN2(bbox[2] + ctx->ViewportArray[i].Height, fb_height);
+      _mesa_intersect_scissor_bounding_box(ctx, i, bbox);
+
+      if (bbox[0] == bbox[1] || bbox[2] == bbox[3]) {
+         /* If the scissor was out of bounds and got clamped to 0 width/height
+          * at the bounds, the subtraction of 1 from maximums could produce a
+          * negative number and thus not clip anything.  Instead, just provide
+          * a min > max scissor inside the bounds, which produces the expected
+          * no rendering.
+          */
+         scissor.ScissorRectangleXMin = 1;
+         scissor.ScissorRectangleXMax = 0;
+         scissor.ScissorRectangleYMin = 1;
+         scissor.ScissorRectangleYMax = 0;
+      } else if (render_to_fbo) {
+         /* texmemory: Y=0=bottom */
+         scissor.ScissorRectangleXMin = bbox[0];
+         scissor.ScissorRectangleXMax = bbox[1] - 1;
+         scissor.ScissorRectangleYMin = bbox[2];
+         scissor.ScissorRectangleYMax = bbox[3] - 1;
+      } else {
+         /* memory: Y=0=top */
+         scissor.ScissorRectangleXMin = bbox[0];
+         scissor.ScissorRectangleXMax = bbox[1] - 1;
+         scissor.ScissorRectangleYMin = fb_height - bbox[3];
+         scissor.ScissorRectangleYMax = fb_height - bbox[2] - 1;
+      }
+
+      GENX(SCISSOR_RECT_pack)(NULL, scissor_map + i * 2, &scissor);
+   }
+
+   brw_batch_emit(brw, GENX(3DSTATE_SCISSOR_STATE_POINTERS), ptr) {
+      ptr.ScissorRectPointer = scissor_state_offset;
+   }
+}
+
+static const struct brw_tracked_state genX(scissor_state) = {
+   .dirty = {
+      .mesa = _NEW_BUFFERS |
+              _NEW_SCISSOR |
+              _NEW_VIEWPORT,
+      .brw = BRW_NEW_BATCH |
+             BRW_NEW_BLORP |
+             BRW_NEW_VIEWPORT_COUNT,
+   },
+   .emit = genX(upload_scissor_state),
+};
+
 /* ---------------------------------------------------------------------- */
 
 void
@@ -2718,7 +2799,7 @@ genX(init_atoms)(struct brw_context *brw)
       &genX(sf_state),
       &genX(wm_state),
 
-      &gen6_scissor_state,
+      &genX(scissor_state),
 
       &gen6_binding_table_pointers,
 
@@ -2808,7 +2889,7 @@ genX(init_atoms)(struct brw_context *brw)
       &genX(wm_state),
       &genX(ps_state),
 
-      &gen6_scissor_state,
+      &genX(scissor_state),
 
       &gen7_depthbuffer,
 
@@ -2899,7 +2980,7 @@ genX(init_atoms)(struct brw_context *brw)
       &genX(depth_stencil_state),
       &genX(wm_state),
 
-      &gen6_scissor_state,
+      &genX(scissor_state),
 
       &gen7_depthbuffer,
 
-- 
git-series 0.9.1