Vulkan:Return HW's SUBPIXEL_BITS

src/libANGLE/Caps.cpp

@@ -1079,6 +1079,8 @@ Caps::Caps()
       maxGeometryTotalOutputComponents(0),
       maxGeometryShaderInvocations(0),
 
+      subPixelBits(4),
+
       // GLES1 emulation: Table 6.20 / 6.22 (ES 1.1 spec)
       maxMultitextureUnits(0),
       maxClipPlanes(0),

src/libANGLE/Caps.h

@@ -693,6 +693,8 @@ struct Caps
     GLuint maxGeometryTotalOutputComponents;
     GLuint maxGeometryShaderInvocations;
 
+    GLuint subPixelBits;
+
     // GLES1 emulation: Caps for ES 1.1. Taken from Table 6.20 / 6.22 in the OpenGL ES 1.1 spec.
     GLuint maxMultitextureUnits;
     GLuint maxClipPlanes;

src/libANGLE/Context.cpp

@@ -1462,7 +1462,7 @@ void Context::getIntegervImpl(GLenum pname, GLint *params)
             *params = mState.mCaps.maxDrawBuffers;
             break;
         case GL_SUBPIXEL_BITS:
-            *params = 4;
+            *params = mState.mCaps.subPixelBits;
             break;
         case GL_MAX_TEXTURE_SIZE:
             *params = mState.mCaps.max2DTextureSize;

src/libANGLE/renderer/vulkan/vk_caps_utils.cpp

@@ -194,6 +194,8 @@ void RendererVk::ensureCapsInitialized() const
     mNativeCaps.maxVaryingVectors =
         (mPhysicalDeviceProperties.limits.maxVertexOutputComponents / 4) - kReservedVaryingCount;
     mNativeCaps.maxVertexOutputComponents = mNativeCaps.maxVaryingVectors * 4;
+
+    mNativeCaps.subPixelBits = mPhysicalDeviceProperties.limits.subPixelPrecisionBits;
 }
 
 namespace egl_vk