Enable stencil clipping in mixed sampled render targets

src/gpu/gl/GrGLGpu.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLGpu.h"
 #include "GrGLGLSL.h"
@@ skipping 263 matching lines @@
     fCopyProgram.fProgram = 0;
     if (this->glCaps().shaderCaps()->pathRenderingSupport()) {
         this->glPathRendering()->abandonGpuResources();
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 void GrGLGpu::onResetContext(uint32_t resetBits) {
     // we don't use the zb at all
     if (resetBits & kMisc_GrGLBackendState) {

[Kimmo Kinnunen, 2015/09/29 12:45:24]

The sample locations are probably part of GL state, similar to any other GL
state.

So the clients might change GL state between Skia calls. For example, they might
change the DepthMask. Similarly, they might change sample locations.

When client has changed GL state, they issue context reset, so that Skia forces
its view of GL state to the GL.

Thus, you probably need to program  the sample locations to 0.5, 0.5 here, even
though that's the GL default.

[Kimmo Kinnunen, 2015/09/29 12:53:37]

Ah, never mind. The sample locations state is per fbo, and that can not be
changed by the client. 

         GL_CALL(Disable(GR_GL_DEPTH_TEST));
         GL_CALL(DepthMask(GR_GL_FALSE));
 
         fHWDrawFace = GrPipelineBuilder::kInvalid_DrawFace;
 
         if (kGL_GrGLStandard == this->glStandard()) {
             // Desktop-only state that we never change
             if (!this->glCaps().isCoreProfile()) {
                 GL_CALL(Disable(GR_GL_POINT_SMOOTH));
                 GL_CALL(Disable(GR_GL_LINE_SMOOTH));
@@ skipping 1174 matching lines @@
 
     int numTextureAccesses = textureAccesses.count();
     for (int i = 0; i < numTextureAccesses; i++) {
         this->bindTexture(i, textureAccesses[i]->getParams(),
                           static_cast<GrGLTexture*>(textureAccesses[i]->getTexture()));
     }
 
     GrGLRenderTarget* glRT = static_cast<GrGLRenderTarget*>(pipeline.getRenderTarget());
     this->flushStencil(pipeline.getStencil());
     this->flushScissor(pipeline.getScissorState(), glRT->getViewport(), glRT->origin());
-    this->flushHWAAState(glRT, pipeline.isHWAntialiasState());
+    this->flushHWAAState(glRT, pipeline.isHWAntialiasState(), !pipeline.getStencil().isDisabled());
 
     // This must come after textures are flushed because a texture may need
     // to be msaa-resolved (which will modify bound FBO state).
     this->flushRenderTarget(glRT, nullptr);
 
     return true;
 }
 
 void GrGLGpu::setupGeometry(const GrPrimitiveProcessor& primProc,
                             const GrNonInstancedVertices& vertices,
@@ skipping 402 matching lines @@
             if (!flipY) {
                 dst += rowBytes;
             } else {
                 dst -= rowBytes;
             }
         }
     }
     return true;
 }
 
+void GrGLGpu::setColocatedSampleLocations(GrRenderTarget* rt, bool useColocatedSampleLocations) {
+    GrGLRenderTarget* target = static_cast<GrGLRenderTarget*>(rt->asRenderTarget());
+    SkASSERT(0 != target->renderFBOID());
+
+    if (!rt->isStencilBufferMultisampled() ||
+        useColocatedSampleLocations == rt->renderTargetPriv().usesColocatedSampleLocations()) {
+        return;
+    }
+
+    GL_CALL(NamedFramebufferParameteri(target->renderFBOID(),
+                                       GR_GL_FRAMEBUFFER_PROGRAMMABLE_SAMPLE_LOCATIONS, useColocatedSampleLocations));

[bsalomon, 2015/09/29 17:41:57]

nit: wrap

[vbuzinov, 2015/09/30 06:08:29]

Done.

+
+    rt->renderTargetPriv().flagAsUsingColocatedSampleLocations(useColocatedSampleLocations);
+}
+
 void GrGLGpu::flushRenderTarget(GrGLRenderTarget* target, const SkIRect* bound) {
 
     SkASSERT(target);
 
     uint32_t rtID = target->getUniqueID();
     if (fHWBoundRenderTargetUniqueID != rtID) {
         fStats.incRenderTargetBinds();
         GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, target->renderFBOID()));
 #ifdef SK_DEBUG
         // don't do this check in Chromium -- this is causing
@@ skipping 227 matching lines @@
                 set_gl_stencil(this->glInterface(),
                                stencilSettings,
                                GR_GL_FRONT_AND_BACK,
                                GrStencilSettings::kFront_Face);
             }
         }
         fHWStencilSettings = stencilSettings;
     }
 }
 
-void GrGLGpu::flushHWAAState(GrRenderTarget* rt, bool useHWAA) {
+void GrGLGpu::flushHWAAState(GrRenderTarget* rt, bool useHWAA, bool stencilEnabled) {
     SkASSERT(!useHWAA || rt->isStencilBufferMultisampled());
 
+    if (rt->hasMixedSamples() && stencilEnabled &&
+        this->glCaps().glslCaps()->programmableSampleLocationsSupport()) {
+        if (useHWAA) {
+            setColocatedSampleLocations(rt, false);

[bsalomon, 2015/09/29 17:41:57]

this->

[vbuzinov, 2015/09/30 06:08:29]

Done.

+        } else {
+            setColocatedSampleLocations(rt, true);

[bsalomon, 2015/09/29 17:41:57]

this->

[vbuzinov, 2015/09/30 06:08:29]

Done.

+        }
+        useHWAA = true;
+    }
+
     if (this->glCaps().multisampleDisableSupport()) {
         if (useHWAA) {
             if (kYes_TriState != fMSAAEnabled) {
                 GL_CALL(Enable(GR_GL_MULTISAMPLE));
                 fMSAAEnabled = kYes_TriState;
             }
         } else {
             if (kNo_TriState != fMSAAEnabled) {
                 GL_CALL(Disable(GR_GL_MULTISAMPLE));
                 fMSAAEnabled = kNo_TriState;
@@ skipping 747 matching lines @@
 
     GL_CALL(Uniform4f(fCopyProgram.fPosXformUniform, dx1 - dx0, dy1 - dy0, dx0, dy0));
     GL_CALL(Uniform4f(fCopyProgram.fTexCoordXformUniform, sx1 - sx0, sy1 - sy0, sx0, sy0));
     GL_CALL(Uniform1i(fCopyProgram.fTextureUniform, 0));
 
     GrXferProcessor::BlendInfo blendInfo;
     blendInfo.reset();
     this->flushBlend(blendInfo);
     this->flushColorWrite(true);
     this->flushDrawFace(GrPipelineBuilder::kBoth_DrawFace);
-    this->flushHWAAState(dstRT, false);
+    this->flushHWAAState(dstRT, false, false);
     this->disableScissor();
     GrStencilSettings stencil;
     stencil.setDisabled();
     this->flushStencil(stencil);
 
     GL_CALL(DrawArrays(GR_GL_TRIANGLE_STRIP, 0, 4));
 }
 
 void GrGLGpu::copySurfaceAsCopyTexSubImage(GrSurface* dst,
                                            GrSurface* src,
@@ skipping 214 matching lines @@
             this->setVertexArrayID(gpu, 0);
         }
         int attrCount = gpu->glCaps().maxVertexAttributes();
         if (fDefaultVertexArrayAttribState.count() != attrCount) {
             fDefaultVertexArrayAttribState.resize(attrCount);
         }
         attribState = &fDefaultVertexArrayAttribState;
     }
     return attribState;
 }