Mesa (master): mesa: Implement ext_framebuffer_multisample_blit_scaled extension

[Anuj Phogat]

Module: Mesa
Branch: master
Commit: 40e3298125e820da7aaad05f3bf23534e6a773ff
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=40e3298125e820da7aaad05f3bf23534e6a773ff

Author: Anuj Phogat <anuj.phogat at gmail.com>
Date:   Thu Apr 18 16:31:35 2013 -0700

mesa: Implement ext_framebuffer_multisample_blit_scaled extension

Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
Reviewed-by: Paul Berry <stereotype441 at gmail.com>
Reviewed-by: Brian Paul <brianp at vmware.com>

---

 src/mesa/main/extensions.c |    1 +
 src/mesa/main/fbobject.c   |   36 ++++++++++++++++++++++++++++++------
 src/mesa/main/mtypes.h     |    1 +
 3 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index db5a5ed..39aaad4 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -184,6 +184,7 @@ static const struct extension extension_table[] = {
    { "GL_EXT_fog_coord",                           o(EXT_fog_coord),                           GLL,            1999 },
    { "GL_EXT_framebuffer_blit",                    o(EXT_framebuffer_blit),                    GL,             2005 },
    { "GL_EXT_framebuffer_multisample",             o(EXT_framebuffer_multisample),             GL,             2005 },
+   { "GL_EXT_framebuffer_multisample_blit_scaled", o(EXT_framebuffer_multisample_blit_scaled), GL,             2011 },
    { "GL_EXT_framebuffer_object",                  o(EXT_framebuffer_object),                  GL,             2000 },
    { "GL_EXT_framebuffer_sRGB",                    o(EXT_framebuffer_sRGB),                    GL,             1998 },
    { "GL_EXT_gpu_program_parameters",              o(EXT_gpu_program_parameters),              GLL,            2006 },
diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index 7c13421..39fa242 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -2980,6 +2980,20 @@ compatible_resolve_formats(const struct gl_renderbuffer *readRb,
    return GL_FALSE;
 }
 
+static GLboolean
+is_valid_blit_filter(const struct gl_context *ctx, GLenum filter)
+{
+   switch (filter) {
+   case GL_NEAREST:
+   case GL_LINEAR:
+      return true;
+   case GL_SCALED_RESOLVE_FASTEST_EXT:
+   case GL_SCALED_RESOLVE_NICEST_EXT:
+      return ctx->Extensions.EXT_framebuffer_multisample_blit_scaled;
+   default:
+      return false;
+   }
+}
 
 /**
  * Blit rectangular region, optionally from one framebuffer to another.
@@ -3029,8 +3043,17 @@ _mesa_BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
       return;
    }
 
-   if (filter != GL_NEAREST && filter != GL_LINEAR) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "glBlitFramebufferEXT(filter)");
+   if (!is_valid_blit_filter(ctx, filter)) {
+      _mesa_error(ctx, GL_INVALID_ENUM, "glBlitFramebufferEXT(%s)",
+                  _mesa_lookup_enum_by_nr(filter));
+      return;
+   }
+
+   if ((filter == GL_SCALED_RESOLVE_FASTEST_EXT ||
+        filter == GL_SCALED_RESOLVE_NICEST_EXT) &&
+        (readFb->Visual.samples == 0 || drawFb->Visual.samples > 0)) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "glBlitFramebufferEXT(%s)",
+                  _mesa_lookup_enum_by_nr(filter));
       return;
    }
 
@@ -3102,10 +3125,10 @@ _mesa_BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                }
             }
          }
-         if (filter == GL_LINEAR) {
-            /* 3.1 spec, page 199:
+         if (filter != GL_NEAREST) {
+            /* From EXT_framebuffer_multisample_blit_scaled specification:
              * "Calling BlitFramebuffer will result in an INVALID_OPERATION error
-             * if filter is LINEAR and read buffer contains integer data."
+             * if filter is not NEAREST and read buffer contains integer data."
              */
             GLenum type = _mesa_get_format_datatype(colorReadRb->Format);
             if (type == GL_INT || type == GL_UNSIGNED_INT) {
@@ -3263,7 +3286,8 @@ _mesa_BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
       }
 
       /* extra checks for multisample copies... */
-      if (readFb->Visual.samples > 0 || drawFb->Visual.samples > 0) {
+      if ((readFb->Visual.samples > 0 || drawFb->Visual.samples > 0) &&
+          (filter == GL_NEAREST || filter == GL_LINEAR)) {
          /* src and dest region sizes must be the same */
          if (abs(srcX1 - srcX0) != abs(dstX1 - dstX0) ||
              abs(srcY1 - srcY0) != abs(dstY1 - dstY0)) {
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 882ebe1..186f8a0 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -3038,6 +3038,7 @@ struct gl_extensions
    GLboolean EXT_fog_coord;
    GLboolean EXT_framebuffer_blit;
    GLboolean EXT_framebuffer_multisample;
+   GLboolean EXT_framebuffer_multisample_blit_scaled;
    GLboolean EXT_framebuffer_object;
    GLboolean EXT_framebuffer_sRGB;
    GLboolean EXT_gpu_program_parameters;