From f253d83bc72e7d26df8cd3a04747b3d46a8543e6 Mon Sep 17 00:00:00 2001
From: Christoph Bumiller <e0425955@student.tuwien.ac.at>
Date: Wed, 3 Aug 2011 16:01:41 +0200
Subject: [PATCH] st/mesa: implement multisample resolve via BlitFramebuffer

---
 src/mesa/state_tracker/st_cb_blit.c | 116 ++++++++++++++++++++++++++++++++++--
 1 file changed, 111 insertions(+), 5 deletions(-)

diff --git a/src/mesa/state_tracker/st_cb_blit.c b/src/mesa/state_tracker/st_cb_blit.c
index 416be19..276d10f 100644
--- a/src/mesa/state_tracker/st_cb_blit.c
+++ b/src/mesa/state_tracker/st_cb_blit.c
@@ -62,6 +62,81 @@ st_destroy_blit(struct st_context *st)
 #if FEATURE_EXT_framebuffer_blit
 
 static void
+st_BlitFramebuffer_resolve(struct gl_context *ctx,
+                           GLbitfield mask,
+                           struct pipe_resolve_info *info)
+{
+   const GLbitfield depthStencil = GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT;
+
+   struct st_context *st = st_context(ctx);
+
+   struct st_renderbuffer *srcRb, *dstRb;
+
+   if (mask & GL_COLOR_BUFFER_BIT) {
+      srcRb = st_renderbuffer(ctx->ReadBuffer->_ColorReadBuffer);
+      dstRb = st_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]);
+
+      info->mask = PIPE_MASK_RGBA;
+
+      info->src.res = srcRb->texture;
+      info->src.layer = srcRb->surface->u.tex.first_layer;
+      info->dst.res = dstRb->texture;
+      info->dst.level = dstRb->surface->u.tex.level;
+      info->dst.layer = dstRb->surface->u.tex.first_layer;
+
+      st->pipe->resource_resolve(st->pipe, info);
+   }
+
+   if (mask & depthStencil) {
+      struct gl_renderbuffer_attachment *srcDepth, *srcStencil;
+      struct gl_renderbuffer_attachment *dstDepth, *dstStencil;
+
+      srcDepth = &ctx->ReadBuffer->Attachment[BUFFER_DEPTH];
+      dstDepth = &ctx->DrawBuffer->Attachment[BUFFER_DEPTH];
+      srcStencil = &ctx->ReadBuffer->Attachment[BUFFER_STENCIL];
+      dstStencil = &ctx->DrawBuffer->Attachment[BUFFER_STENCIL];
+
+      const boolean combined =
+         st_is_depth_stencil_combined(srcDepth, srcStencil) &&
+         st_is_depth_stencil_combined(dstDepth, dstStencil);
+
+      if ((mask & GL_DEPTH_BUFFER_BIT) || combined) {
+         /* resolve depth and, if combined and requested, stencil as well */
+         srcRb = st_renderbuffer(srcDepth->Renderbuffer);
+         dstRb = st_renderbuffer(dstDepth->Renderbuffer);
+
+         info->mask = (mask & GL_DEPTH_BUFFER_BIT) ? PIPE_MASK_Z : 0;
+         if (combined && (mask & GL_STENCIL_BUFFER_BIT))
+            info->mask |= PIPE_MASK_S;
+
+         info->src.res = srcRb->texture;
+         info->src.layer = srcRb->surface->u.tex.first_layer;
+         info->dst.res = dstRb->texture;
+         info->dst.level = dstRb->surface->u.tex.level;
+         info->dst.layer = dstRb->surface->u.tex.first_layer;
+
+         st->pipe->resource_resolve(st->pipe, info);
+      }
+
+      if (mask & GL_STENCIL_BUFFER_BIT) {
+         /* resolve separate stencil buffer */
+         srcRb = st_renderbuffer(srcStencil->Renderbuffer);
+         dstRb = st_renderbuffer(dstStencil->Renderbuffer);
+
+         info->mask = PIPE_MASK_S;
+
+         info->src.res = srcRb->texture;
+         info->src.layer = srcRb->surface->u.tex.first_layer;
+         info->dst.res = dstRb->texture;
+         info->dst.level = dstRb->surface->u.tex.level;
+         info->dst.layer = dstRb->surface->u.tex.first_layer;
+
+         st->pipe->resource_resolve(st->pipe, info);
+      }
+   }
+}
+
+static void
 st_BlitFramebuffer(struct gl_context *ctx,
                    GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                    GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
@@ -95,6 +170,42 @@ st_BlitFramebuffer(struct gl_context *ctx,
       srcY1 = readFB->Height - srcY1;
    }
 
+   /* Disable conditional rendering. */
+   if (st->render_condition) {
+      st->pipe->render_condition(st->pipe, NULL, 0);
+   }
+
+   if (readFB->Visual.sampleBuffers > drawFB->Visual.sampleBuffers) {
+      struct pipe_resolve_info info;
+
+      if (dstX0 < dstX1) {
+         info.dst.x0 = dstX0;
+         info.dst.x1 = dstX1;
+         info.src.x0 = srcX0;
+         info.src.x1 = srcX1;
+      } else {
+         info.dst.x0 = dstX1;
+         info.dst.x1 = dstX0;
+         info.src.x0 = srcX1;
+         info.src.x1 = srcX0;
+      }
+      if (dstY0 < dstY1) {
+         info.dst.y0 = dstY0;
+         info.dst.y1 = dstY1;
+         info.src.y0 = srcY0;
+         info.src.y1 = srcY1;
+      } else {
+         info.dst.y0 = dstY1;
+         info.dst.y1 = dstY0;
+         info.src.y0 = srcY1;
+         info.src.y1 = srcY0;
+      }
+
+      st_BlitFramebuffer_resolve(ctx, mask, &info); /* filter doesn't apply */
+
+      goto done;
+   }
+
    if (srcY0 > srcY1 && dstY0 > dstY1) {
       /* Both src and dst are upside down.  Swap Y to make it
        * right-side up to increase odds of using a fast path.
@@ -109,11 +220,6 @@ st_BlitFramebuffer(struct gl_context *ctx,
       dstY1 = tmp;
    }
 
-   /* Disable conditional rendering. */
-   if (st->render_condition) {
-      st->pipe->render_condition(st->pipe, NULL, 0);
-   }
-
    if (mask & GL_COLOR_BUFFER_BIT) {
       struct gl_renderbuffer_attachment *srcAtt =
          &readFB->Attachment[readFB->_ColorReadBufferIndex];
-- 
2.7.4