Avoid setting the GL color mask and clear color redundantly before glClear.

Change-Id: I0830e62fc65fd4a85c27db01aab8e16697c840f7
Reviewed-on: https://skia-review.googlesource.com/c/187304
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

2 files changed, 21 insertions, 8 deletions

diff --git a/src/gpu/gl/GrGLGpu.cpp b/src/gpu/gl/GrGLGpu.cpp
index 02df297de5..4a03a26400 100644
--- a/src/gpu/gl/GrGLGpu.cpp
+++ b/src/gpu/gl/GrGLGpu.cpp
@@ -540,6 +540,8 @@ void GrGLGpu::onResetContext(uint32_t resetBits) {
         // we only ever use lines in hairline mode
         GL_CALL(LineWidth(1));
         GL_CALL(Disable(GR_GL_DITHER));
+
+        fHWClearColor[0] = fHWClearColor[1] = fHWClearColor[2] = fHWClearColor[3] = SK_FloatNaN;
     }
 
     if (resetBits & kMSAAEnable_GrGLBackendState) {
@@ -1615,9 +1617,8 @@ sk_sp<GrTexture> GrGLGpu::onCreateTexture(const GrSurfaceDesc& desc,
                                             kDst_TempFBOTarget);
             this->disableScissor();
             this->disableWindowRectangles();
-            GL_CALL(ColorMask(GR_GL_TRUE, GR_GL_TRUE, GR_GL_TRUE, GR_GL_TRUE));
-            fHWWriteToColor = kYes_TriState;
-            GL_CALL(ClearColor(0, 0, 0, 0));
+            this->flushColorWrite(true);
+            this->flushClearColor(0, 0, 0, 0);
             GL_CALL(Clear(GR_GL_COLOR_BUFFER_BIT));
             this->unbindTextureFBOForPixelOps(GR_GL_FRAMEBUFFER, tex.get());
             fHWBoundRenderTargetUniqueID.makeInvalid();
@@ -2164,19 +2165,17 @@ void GrGLGpu::clear(const GrFixedClip& clip, const SkPMColor4f& color,
     }
     this->flushScissor(clip.scissorState(), glRT->getViewport(), origin);
     this->flushWindowRectangles(clip.windowRectsState(), glRT, origin);
-
-    GL_CALL(ColorMask(GR_GL_TRUE, GR_GL_TRUE, GR_GL_TRUE, GR_GL_TRUE));
-    fHWWriteToColor = kYes_TriState;
+    this->flushColorWrite(true);
 
     GrGLfloat r = color.fR, g = color.fG, b = color.fB, a = color.fA;
-
     if (this->glCaps().clearToBoundaryValuesIsBroken() &&
         (1 == r || 0 == r) && (1 == g || 0 == g) && (1 == b || 0 == b) && (1 == a || 0 == a)) {
         static const GrGLfloat safeAlpha1 = nextafter(1.f, 2.f);
         static const GrGLfloat safeAlpha0 = nextafter(0.f, -1.f);
         a = (1 == a) ? safeAlpha1 : safeAlpha0;
     }
-    GL_CALL(ClearColor(r, g, b, a));
+    this->flushClearColor(r, g, b, a);
+
     GL_CALL(Clear(GR_GL_COLOR_BUFFER_BIT));
 }
 
@@ -3095,6 +3094,17 @@ void GrGLGpu::flushColorWrite(bool writeColor) {
     }
 }
 
+void GrGLGpu::flushClearColor(GrGLfloat r, GrGLfloat g, GrGLfloat b, GrGLfloat a) {
+    if (r != fHWClearColor[0] || g != fHWClearColor[1] ||
+        b != fHWClearColor[2] || a != fHWClearColor[3]) {
+        GL_CALL(ClearColor(r, g, b, a));
+        fHWClearColor[0] = r;
+        fHWClearColor[1] = g;
+        fHWClearColor[2] = b;
+        fHWClearColor[3] = a;
+    }
+}
+
 void GrGLGpu::setTextureUnit(int unit) {
     SkASSERT(unit >= 0 && unit < fHWBoundTextureUniqueIDs.count());
     if (unit != fHWActiveTextureUnitIdx) {
diff --git a/src/gpu/gl/GrGLGpu.h b/src/gpu/gl/GrGLGpu.h
index e97ed7a185..eb721b361d 100644
--- a/src/gpu/gl/GrGLGpu.h
+++ b/src/gpu/gl/GrGLGpu.h
@@ -338,6 +338,7 @@ private:
     };
 
     void flushColorWrite(bool writeColor);
+    void flushClearColor(GrGLfloat r, GrGLfloat g, GrGLfloat b, GrGLfloat a);
 
     // flushes the scissor. see the note on flushBoundTextureAndParams about
     // flushing the scissor after that function is called.
@@ -587,6 +588,8 @@ private:
     TriState                                fHWSRGBFramebuffer;
     SkTArray<GrGpuResource::UniqueID, true> fHWBoundTextureUniqueIDs;
 
+    GrGLfloat fHWClearColor[4];
+
     GrGLuint fBoundDrawFramebuffer = 0;
 
     // EXT_raster_multisample.