Revert "Initial OpenGL Image support."

This reverts commit be34882042048db096baca32ddf4a8b472529804.

Reason for revert: Test failures and shader compilation issues on Android.

Original change's description:
> Initial OpenGL Image support.
> 
> This change along with recently landed changes is enough to make the new unit test work and not much else. imageLoad is support but not stores or any other image functions (atomics). Barriers in the shading language or the GL API are not yet hooked up.
> 
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4182
> 
> Change-Id: I5958b7c89e40ae5ee05f7bbaca3b3738162fe5ce
> Reviewed-on: https://skia-review.googlesource.com/4182
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Reviewed-by: Chris Dalton <csmartdalton@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>
> 

TBR=egdaniel@google.com,bsalomon@google.com,csmartdalton@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I29a2502c296ae39ed9a999957800414ae46e6f0f
Reviewed-on: https://skia-review.googlesource.com/5129
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 32 insertions, 72 deletions

diff --git a/src/gpu/GrProgramDesc.cpp b/src/gpu/GrProgramDesc.cpp
index 9f3278c927..cdbbc23534 100644
--- a/src/gpu/GrProgramDesc.cpp
+++ b/src/gpu/GrProgramDesc.cpp
@@ -15,88 +15,48 @@
 #include "glsl/GrGLSLFragmentShaderBuilder.h"
 #include "glsl/GrGLSLCaps.h"
 
-enum {
-    kSamplerOrImageTypeKeyBits = 4
-};
-
-static inline uint16_t image_storage_or_sampler_uniform_type_key(GrSLType type ) {
-    int value = UINT16_MAX;
-    switch (type) {
-        case kTexture2DSampler_GrSLType:
-            value = 0;
-            break;
-        case kITexture2DSampler_GrSLType:
-            value = 1;
-            break;
-        case kTextureExternalSampler_GrSLType:
-            value = 2;
-            break;
-        case kTexture2DRectSampler_GrSLType:
-            value = 3;
-            break;
-        case kBufferSampler_GrSLType:
-            value = 4;
-            break;
-        case kImageStorage2D_GrSLType:
-            value = 5;
-            break;
-        case kIImageStorage2D_GrSLType:
-            value = 6;
-            break;
-
-        default:
-            break;
-    }
-    SkASSERT((value & ((1 << kSamplerOrImageTypeKeyBits) - 1)) == value);
-    return value;
-}
-
 static uint16_t sampler_key(GrSLType samplerType, GrPixelConfig config, GrShaderFlags visibility,
                             const GrGLSLCaps& caps) {
-    int samplerTypeKey = image_storage_or_sampler_uniform_type_key(samplerType);
-
-    GR_STATIC_ASSERT(1 == sizeof(caps.configTextureSwizzle(config).asKey()));
-    return SkToU16(samplerTypeKey |
-                   caps.configTextureSwizzle(config).asKey() << kSamplerOrImageTypeKeyBits |
-                   (caps.samplerPrecision(config, visibility) << (8 + kSamplerOrImageTypeKeyBits)));
+    enum {
+        kFirstSamplerType = kTexture2DSampler_GrSLType,
+        kLastSamplerType = kBufferSampler_GrSLType,
+        kSamplerTypeKeyBits = 4
+    };
+    GR_STATIC_ASSERT(kLastSamplerType - kFirstSamplerType < (1 << kSamplerTypeKeyBits));
+
+    SkASSERT((int)samplerType >= kFirstSamplerType && (int)samplerType <= kLastSamplerType);
+    int samplerTypeKey = samplerType - kFirstSamplerType;
+
+    return SkToU16(caps.configTextureSwizzle(config).asKey() |
+                   (samplerTypeKey << 8) |
+                   (caps.samplerPrecision(config, visibility) << (8 + kSamplerTypeKeyBits)));
 }
 
-static uint16_t storage_image_key(const GrProcessor::ImageStorageAccess& imageAccess) {
-    GrSLType type = imageAccess.texture()->texturePriv().imageStorageType();
-    return image_storage_or_sampler_uniform_type_key(type) |
-           (int)imageAccess.format() << kSamplerOrImageTypeKeyBits;
-}
-
-static void add_sampler_and_image_keys(GrProcessorKeyBuilder* b, const GrProcessor& proc,
-                                       const GrGLSLCaps& caps) {
+static void add_sampler_keys(GrProcessorKeyBuilder* b, const GrProcessor& proc,
+                             const GrGLSLCaps& caps) {
     int numTextureSamplers = proc.numTextureSamplers();
-    int numBuffers = proc.numBuffers();
-    int numImageStorages = proc.numImageStorages();
-    int numUniforms = numTextureSamplers + numBuffers + numImageStorages;
-    // Need two bytes per key.
-    int word32Count = (numUniforms + 1) / 2;
+    int numSamplers = numTextureSamplers + proc.numBuffers();
+    // Need two bytes per key (swizzle, sampler type, and precision).
+    int word32Count = (numSamplers + 1) / 2;
     if (0 == word32Count) {
         return;
     }
     uint16_t* k16 = SkTCast<uint16_t*>(b->add32n(word32Count));
-    int j = 0;
-    for (int i = 0; i < numTextureSamplers; ++i, ++j) {
-        const GrProcessor::TextureSampler& sampler = proc.textureSampler(i);
-        const GrTexture* tex = sampler.texture();
-        k16[j] = sampler_key(tex->texturePriv().samplerType(), tex->config(), sampler.visibility(),
-                             caps);
-    }
-    for (int i = 0; i < numBuffers; ++i, ++j) {
-        const GrProcessor::BufferAccess& access = proc.bufferAccess(i);
-        k16[j] = sampler_key(kBufferSampler_GrSLType, access.texelConfig(), access.visibility(),
-                             caps);
+    int i = 0;
+    for (; i < numTextureSamplers; ++i) {
+        const GrProcessor::TextureSampler& textureSampler = proc.textureSampler(i);
+        const GrTexture* tex = textureSampler.texture();
+        k16[i] = sampler_key(tex->texturePriv().samplerType(), tex->config(),
+                             textureSampler.visibility(), caps);
     }
-    for (int i = 0; i < numImageStorages; ++i, ++j) {
-        k16[j] = storage_image_key(proc.imageStorageAccess(i));
+    for (; i < numSamplers; ++i) {
+        const GrProcessor::BufferAccess& access = proc.bufferAccess(i - numTextureSamplers);
+        k16[i] = sampler_key(kBufferSampler_GrSLType, access.texelConfig(),
+                             access.visibility(), caps);
     }
-    // zero the last 16 bits if the number of uniforms for samplers and image storages is odd.
-    if (numUniforms & 0x1) {
-        k16[numUniforms] = 0;
+    // zero the last 16 bits if the number of samplers is odd.
+    if (numSamplers & 0x1) {
+        k16[numSamplers] = 0;
     }
 }
 
@@ -122,7 +82,7 @@ static bool gen_meta_key(const GrProcessor& proc,
         return false;
     }
 
-    add_sampler_and_image_keys(b, proc, glslCaps);
+    add_sampler_keys(b, proc, glslCaps);
 
     uint32_t* key = b->add32n(2);
     key[0] = (classID << 16) | SkToU32(processorKeySize);