Support GL_SAMPLES queries in null contexts

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2085043002

Committed: https://skia.googlesource.com/skia/+/64b92a59294a2f73448b3fa8f36f39079f032521
Committed: https://skia.googlesource.com/skia/+/57e98530c113066c4c2d9c64505c52dc25e66c00
Review-Url: https://codereview.chromium.org/2085043002

3 files changed, 87 insertions, 3 deletions

diff --git a/tools/gpu/gl/debug/DebugGLTestContext.cpp b/tools/gpu/gl/debug/DebugGLTestContext.cpp
index 022d56a452..cf8a9e4240 100644
--- a/tools/gpu/gl/debug/DebugGLTestContext.cpp
+++ b/tools/gpu/gl/debug/DebugGLTestContext.cpp
@@ -373,6 +373,34 @@ public:
         }
     }
 
+    GrGLvoid renderbufferStorage(GrGLenum target, GrGLenum internalformat, GrGLsizei width,
+                                 GrGLsizei height) override {
+        GrAlwaysAssert(GR_GL_RENDERBUFFER == target);
+        GrRenderBufferObj* renderBuffer = this->getRenderBuffer();
+        GrAlwaysAssert(renderBuffer);
+        renderBuffer->setNumSamples(1);
+    }
+
+    GrGLvoid renderbufferStorageMultisample(GrGLenum target, GrGLsizei samples,
+                                            GrGLenum internalformat, GrGLsizei width,
+                                            GrGLsizei height) override {
+        GrAlwaysAssert(GR_GL_RENDERBUFFER == target);
+        GrRenderBufferObj* renderBuffer = this->getRenderBuffer();
+        GrAlwaysAssert(renderBuffer);
+        renderBuffer->setNumSamples(samples);
+    }
+
+    GrGLvoid namedRenderbufferStorage(GrGLuint renderbuffer, GrGLenum GrGLinternalformat,
+                                      GrGLsizei width, GrGLsizei height) override {
+        SK_ABORT("Not implemented");
+    }
+
+    GrGLvoid namedRenderbufferStorageMultisample(GrGLuint renderbuffer, GrGLsizei samples,
+                                                 GrGLenum GrGLinternalformat, GrGLsizei width,
+                                                 GrGLsizei height) override {
+        SK_ABORT("Not implemented");
+    }
+
     GrGLvoid framebufferRenderbuffer(GrGLenum target,
                                      GrGLenum attachment,
                                      GrGLenum renderbuffertarget,
@@ -410,6 +438,12 @@ public:
 
     }
 
+    GrGLvoid namedFramebufferRenderbuffer(GrGLuint framebuffer, GrGLenum attachment,
+                                          GrGLenum renderbuffertarget,
+                                          GrGLuint renderbuffer) override {
+        SK_ABORT("Not implemented");
+    }
+
     ////////////////////////////////////////////////////////////////////////////////
     GrGLvoid framebufferTexture2D(GrGLenum target, GrGLenum attachment, GrGLenum textarget,
                                   GrGLuint textureID, GrGLint level) override {
@@ -450,6 +484,30 @@ public:
         };
     }
 
+    GrGLvoid framebufferTexture2DMultisample(GrGLenum target, GrGLenum attachment,
+                                             GrGLenum textarget, GrGLuint texture, GrGLint level,
+                                             GrGLsizei samples) override {
+        SK_ABORT("Not implemented");
+    }
+
+    GrGLvoid namedFramebufferTexture1D(GrGLuint framebuffer, GrGLenum attachment,
+                                       GrGLenum textarget, GrGLuint texture,
+                                       GrGLint level) override {
+        SK_ABORT("Not implemented");
+    }
+
+    GrGLvoid namedFramebufferTexture2D(GrGLuint framebuffer, GrGLenum attachment,
+                                       GrGLenum textarget, GrGLuint texture,
+                                       GrGLint level) override {
+        SK_ABORT("Not implemented");
+    }
+
+    GrGLvoid namedFramebufferTexture3D(GrGLuint framebuffer, GrGLenum attachment,
+                                       GrGLenum textarget, GrGLuint texture, GrGLint level,
+                                       GrGLint zoffset) override {
+        SK_ABORT("Not implemented");
+    }
+
     GrGLuint createProgram() override {
 
         GrProgramObj *program = CREATE(GrProgramObj, kProgram_ObjTypes);
@@ -530,9 +588,26 @@ public:
             case GR_GL_STENCIL_BITS:
                 *params = 8;
                 break;
-            case GR_GL_SAMPLES:
-                *params = 1;
+            case GR_GL_SAMPLES: {
+                GrFrameBufferObj* framebuffer = this->getFrameBuffer();
+                GrAlwaysAssert(framebuffer);
+                int numSamples = 0;
+
+                if (GrFBBindableObj* stencil = framebuffer->getStencil()) {
+                    numSamples = stencil->numSamples();
+                }
+                if (GrFBBindableObj* depth = framebuffer->getDepth()) {
+                    GrAlwaysAssert(!numSamples || numSamples == depth->numSamples());
+                    numSamples = depth->numSamples();
+                }
+                if (GrFBBindableObj* color = framebuffer->getColor()) {
+                    GrAlwaysAssert(!numSamples || numSamples == color->numSamples());
+                    numSamples = color->numSamples();
+                }
+                GrAlwaysAssert(numSamples);
+                *params = numSamples;
                 break;
+            }
             case GR_GL_FRAMEBUFFER_BINDING:
                 *params = 0;
                 break;
diff --git a/tools/gpu/gl/debug/GrFBBindableObj.h b/tools/gpu/gl/debug/GrFBBindableObj.h
index e2b43a6a1b..f5b46ab5d9 100644
--- a/tools/gpu/gl/debug/GrFBBindableObj.h
+++ b/tools/gpu/gl/debug/GrFBBindableObj.h
@@ -18,7 +18,8 @@ class GrFBBindableObj : public GrFakeRefObj {
 
 public:
     GrFBBindableObj()
-        : GrFakeRefObj() {
+        : GrFakeRefObj()
+        , fNumSamples(1) {
     }
 
     virtual ~GrFBBindableObj() {
@@ -75,8 +76,11 @@ public:
         return 0 != fStencilReferees.count();
     }
 
+    int numSamples() { return fNumSamples; }
 
 protected:
+    int fNumSamples;
+
 private:
     SkTDArray<GrFakeRefObj *> fColorReferees;   // frame buffers that use this as a color buffer (via "glFramebufferRenderbuffer" or "glFramebufferTexture2D")
     SkTDArray<GrFakeRefObj *> fDepthReferees;   // frame buffers that use this as a depth buffer (via "glFramebufferRenderbuffer" or "glFramebufferTexture2D")
diff --git a/tools/gpu/gl/debug/GrRenderBufferObj.h b/tools/gpu/gl/debug/GrRenderBufferObj.h
index 8231ef58df..134b9ec763 100644
--- a/tools/gpu/gl/debug/GrRenderBufferObj.h
+++ b/tools/gpu/gl/debug/GrRenderBufferObj.h
@@ -30,6 +30,11 @@ public:
         this->INHERITED::deleteAction();
     }
 
+    void setNumSamples(int numSamples) {
+        GrAlwaysAssert(numSamples > 0);
+        fNumSamples = numSamples;
+    }
+
 protected:
 private:
     bool fBound;           // is this render buffer currently bound via "glBindRenderbuffer"?