commit 8d47ddc19a40d1984bf1f384d711d36ab59fd1c0
author commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> Thu May 09 14:55:46 2013 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> Thu May 09 14:55:46 2013 +0000
tree cca2ab430158fcaaaeb9ba7a3f5653474e8d541a
parent 504976ef6f1b969c2ac13ff1140ea1067f085ffa

Make GrGLShaderBuilder check whether GrEffect advertised that it would require the dst color or fragment position

R=senorblanco@chromium.org, robertphillips@google.com

Author: bsalomon@google.com

Review URL: https://chromiumcodereview.appspot.com/14998007

git-svn-id: http://skia.googlecode.com/svn/trunk@9074 2bbb7eff-a529-9590-31e7-b0007b416f81

src/gpu/gl/GrGLShaderBuilder.cpp

diff --git a/src/gpu/gl/GrGLShaderBuilder.cpp b/src/gpu/gl/GrGLShaderBuilder.cpp
index c1732b2..98d7e4c 100644
--- a/src/gpu/gl/GrGLShaderBuilder.cpp
+++ b/src/gpu/gl/GrGLShaderBuilder.cpp
@@ -230,6 +230,14 @@
 }
 
 const char* GrGLShaderBuilder::dstColor() {
+    if (fCodeStage.inStageCode()) {
+        const GrEffectRef& effect = *fCodeStage.effectStage()->getEffect();
+        if (!effect->willReadDstColor()) {
+            GrDebugCrash("GrGLEffect asked for dst color but its generating GrEffect "
+                         "did not request access.");
+            return "";
+        }
+    }
     static const char kFBFetchColorName[] = "gl_LastFragData[0]";
     GrGLCaps::FBFetchType fetchType = fCtxInfo.caps()->fbFetchType();
     if (GrGLCaps::kEXT_FBFetchType == fetchType) {
@@ -241,7 +249,7 @@
     } else if (fDstCopySampler.isInitialized()) {
         return kDstCopyColorName;
     } else {
-        return NULL;
+        return "";
     }
 }
 
@@ -457,6 +465,14 @@
 }
 
 const char* GrGLShaderBuilder::fragmentPosition() {
+    if (fCodeStage.inStageCode()) {
+        const GrEffectRef& effect = *fCodeStage.effectStage()->getEffect();
+        if (!effect->willReadFragmentPosition()) {
+            GrDebugCrash("GrGLEffect asked for frag position but its generating GrEffect "
+                         "did not request access.");
+            return "";
+        }
+    }
 #if 1
     if (fCtxInfo.caps()->fragCoordConventionsSupport()) {
         if (!fSetupFragPosition) {