framebuffer: add _mesa_get_read_renderbuffer

This returns the current read renderbuffer for the specified
format type.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

diff --git a/src/mesa/main/framebuffer.c b/src/mesa/main/framebuffer.c
index 13887f8f54b1db794b990aa2a53c88267d069f7e..8cbfbd6bcfb67ae269942251a6a16a61b3860d46 100644 (file)
--- a/src/mesa/main/framebuffer.c
+++ b/src/mesa/main/framebuffer.c
@@ -42,6 +42,7 @@
 #include "framebuffer.h"
 #include "renderbuffer.h"
 #include "texobj.h"
+#include "glformats.h"
 
 
 
@@ -898,6 +899,26 @@ _mesa_get_color_read_type(struct gl_context *ctx)
 }
 
 
+/**
+ * Returns the read renderbuffer for the specified format.
+ */
+struct gl_renderbuffer *
+_mesa_get_read_renderbuffer_for_format(struct gl_context *ctx,
+                                       GLenum format)
+{
+   struct gl_framebuffer *rfb = ctx->ReadBuffer;
+
+   if (_mesa_is_color_format(format)) {
+      return rfb->Attachment[rfb->_ColorReadBufferIndex].Renderbuffer;
+   } else if (_mesa_is_depth_format(format) ||
+              _mesa_is_depthstencil_format(format)) {
+      return rfb->Attachment[BUFFER_DEPTH].Renderbuffer;
+   } else {
+      return rfb->Attachment[BUFFER_STENCIL].Renderbuffer;
+   }
+}
+
+
 /**
  * Print framebuffer info to stderr, for debugging.
  */

diff --git a/src/mesa/main/framebuffer.h b/src/mesa/main/framebuffer.h
index ad53d8cbeb039845b0efa0fe62e47faef78906f4..06db04925446634488fe597763bbf7b366614233 100644 (file)
--- a/src/mesa/main/framebuffer.h
+++ b/src/mesa/main/framebuffer.h
@@ -30,6 +30,7 @@
 
 struct gl_config;
 struct gl_context;
+struct gl_renderbuffer;
 
 extern struct gl_framebuffer *
 _mesa_create_framebuffer(const struct gl_config *visual);
@@ -96,6 +97,10 @@ _mesa_get_color_read_type(struct gl_context *ctx);
 extern GLenum
 _mesa_get_color_read_format(struct gl_context *ctx);
 
+extern struct gl_renderbuffer *
+_mesa_get_read_renderbuffer_for_format(struct gl_context *ctx,
+                                       GLenum format);
+
 extern void
 _mesa_print_framebuffer(const struct gl_framebuffer *fb);