Refactor how we store and use samplers in Ganesh

The main goal of this refactorization is to allow Vulkan to use separate
sampler and texture objects in the shader and descriptor sets and combine
them into a sampler2d in the shader where needed.

A large part of this is separating how we store samplers and uniforms in the
UniformHandler. We no longer need to store handles to samplers besides when
we are initially emitting code. After we emit code all we ever do is loop over
all samplers and do some processor independent work on them, so we have no need
for direct access to individual samplers.

In the GLProgram all we ever do is set the sampler uniforms in the ctor and never
touch them again, so no need to save sampler info there. The texture access on
program reuse just assume that they come in the same order as we set the texture
units for the samplers

For Vulkan, it is a similar story. We create the descriptor set layouts with the samplers,
then when we get new textures, we just assume they come in in the same order as we
set the samplers on the descriptor sets. Thus no need to save direct vulkan info.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1885863004

Review URL: https://codereview.chromium.org/1885863004

1 files changed, 8 insertions, 5 deletions

diff --git a/src/gpu/glsl/GrGLSLProgramBuilder.h b/src/gpu/glsl/GrGLSLProgramBuilder.h
index 3ce7daf349..c175fc6adf 100644
--- a/src/gpu/glsl/GrGLSLProgramBuilder.h
+++ b/src/gpu/glsl/GrGLSLProgramBuilder.h
@@ -41,6 +41,10 @@ public:
 
     void appendUniformDecls(GrShaderFlags visibility, SkString*) const;
 
+    typedef GrGLSLUniformHandler::SamplerHandle SamplerHandle;
+
+    const GrGLSLSampler& getSampler(SamplerHandle handle) const;
+
     // Handles for program uniforms (other than per-effect uniforms)
     struct BuiltinUniformHandles {
         UniformHandle       fRTAdjustmentUni;
@@ -104,8 +108,6 @@ protected:
 
     void finalizeShaders();
 
-    SkTArray<UniformHandle> fSamplerUniforms;
-
 private:
     // reset is called by program creator between each processor's emit code.  It increments the
     // stage offset for variable name mangling, and also ensures verfication variables in the
@@ -146,14 +148,15 @@ private:
                                 const GrGLSLExpr4& coverageIn,
                                 bool ignoresCoverage,
                                 GrPixelLocalStorageState plsState);
+
     void emitSamplers(const GrProcessor& processor,
-                      GrGLSLSampler::SamplerArray* outTexSamplers,
-                      GrGLSLSampler::SamplerArray* outBufferSamplers);
+                      SkTArray<SamplerHandle>* outTexSamplers,
+                      SkTArray<SamplerHandle>* outBufferSamplers);
     void emitSampler(GrSLType samplerType,
                      GrPixelConfig,
                      const char* name,
                      GrShaderFlags visibility,
-                     GrGLSLSampler::SamplerArray* outSamplers);
+                     SkTArray<SamplerHandle>* outSamplers);
     void emitFSOutputSwizzle(bool hasSecondaryOutput);
     bool checkSamplerCounts();