Merge pull request #3010 from AnalyticalGraphicsInc/scissor-clear

Always apply the scissor test on clears.
CesiumGS · Sep 9, 2015 · 3c0a524 · 3c0a524
2 parents a6bc070 + b077d0f
commit 3c0a524
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Showing 2 changed files with 10 additions and 7 deletions.
diff --git a/Source/Renderer/Context.js b/Source/Renderer/Context.js
@@ -697,12 +697,12 @@ define([
         }
     }
 
-    function applyRenderState(context, renderState, passState) {
+    function applyRenderState(context, renderState, passState, clear) {
         var previousRenderState = context._currentRenderState;
         var previousPassState = context._currentPassState;
         context._currentRenderState = renderState;
         context._currentPassState = passState;
-        RenderState.partialApply(context._gl, previousRenderState, renderState, previousPassState, passState);
+        RenderState.partialApply(context._gl, previousRenderState, renderState, previousPassState, passState, clear);
     }
 
     var scratchBackBufferArray;
@@ -771,7 +771,7 @@ define([
         }
 
         var rs = defaultValue(clearCommand.renderState, this._defaultRenderState);
-        applyRenderState(this, rs, passState);
+        applyRenderState(this, rs, passState, true);
 
         // The command's framebuffer takes presidence over the pass' framebuffer, e.g., for off-screen rendering.
         var framebuffer = defaultValue(clearCommand.framebuffer, passState.framebuffer);
@@ -793,7 +793,7 @@ define([
 
         bindFramebuffer(context, framebuffer);
 
-        applyRenderState(context, rs, passState);
+        applyRenderState(context, rs, passState, false);
 
         var sp = defaultValue(shaderProgram, drawCommand.shaderProgram);
         sp._bind();

diff --git a/Source/Renderer/RenderState.js b/Source/Renderer/RenderState.js
@@ -661,7 +661,7 @@ define([
         return funcs;
     }
 
-    RenderState.partialApply = function(gl, previousRenderState, renderState, previousPassState, passState) {
+    RenderState.partialApply = function(gl, previousRenderState, renderState, previousPassState, passState, clear) {
         if (previousRenderState !== renderState) {
             // When a new render state is applied, instead of making WebGL calls for all the states or first
             // comparing the states one-by-one with the previous state (basically a linear search), we take
@@ -683,7 +683,10 @@ define([
 
         var previousScissorTest = (defined(previousPassState.scissorTest)) ? previousPassState.scissorTest : previousRenderState.scissorTest;
         var scissorTest = (defined(passState.scissorTest)) ? passState.scissorTest : renderState.scissorTest;
-        if (previousScissorTest !== scissorTest) {
+
+        // Our scissor rectangle can get out of sync with the GL scissor rectangle on clears.
+        // Seems to be a problem only on ANGLE. See https://github.com/AnalyticalGraphicsInc/cesium/issues/2994
+        if ((previousScissorTest !== scissorTest) || clear) {
             applyScissorTest(gl, renderState, passState);
         }
 
@@ -775,4 +778,4 @@ define([
     };
 
     return RenderState;
-});
+});