Add automatic generation of mipmaps to Vulkan

src/gpu/vk/GrVkPipelineState.cpp

Index: src/gpu/vk/GrVkPipelineState.cpp
diff --git a/src/gpu/vk/GrVkPipelineState.cpp b/src/gpu/vk/GrVkPipelineState.cpp
index 0194e290ad351aeb980114885be973768836700e..589dc9984e159e15e385f09de8ea4bfa81b9285e 100644
--- a/src/gpu/vk/GrVkPipelineState.cpp
+++ b/src/gpu/vk/GrVkPipelineState.cpp
@@ -8,6 +8,7 @@
 #include "GrVkPipelineState.h"
 
 #include "GrPipeline.h"
+#include "GrTexturePriv.h"
 #include "GrVkCommandBuffer.h"
 #include "GrVkDescriptorPool.h"
 #include "GrVkGpu.h"
@@ -21,6 +22,7 @@
 #include "glsl/GrGLSLFragmentProcessor.h"
 #include "glsl/GrGLSLGeometryProcessor.h"
 #include "glsl/GrGLSLXferProcessor.h"
+#include "SkMipmap.h"
 
 GrVkPipelineState::GrVkPipelineState(GrVkGpu* gpu,
                                      const GrVkPipelineState::Desc& desc,
@@ -290,9 +292,21 @@ void GrVkPipelineState::writeSamplers(GrVkGpu* gpu,
 
     for (int i = 0; i < textureBindings.count(); ++i) {
         const GrTextureParams& params = textureBindings[i]->getParams();
-        fSamplers.push(gpu->resourceProvider().findOrCreateCompatibleSampler(params));
 
         GrVkTexture* texture = static_cast<GrVkTexture*>(textureBindings[i]->getTexture());
+        if (GrTextureParams::kMipMap_FilterMode == params.filterMode()) {
+            if (texture->texturePriv().mipMapsAreDirty()) {
+                if (gpu->generateMipmap(texture)) {
+                    uint32_t mipLevels = SkMipMap::ComputeLevelCount(texture->width(),
+                                                                     texture->height());
+                    texture->texturePriv().setMaxMipMapLevel(mipLevels);

[egdaniel, 2016/04/25 21:01:09]

can this be done in generateMipmap? Might be able to avoid calling
ComputeLevelCount again.

[jvanverth1, 2016/04/26 14:18:26]

Done.

+                }
+                texture->texturePriv().dirtyMipMaps(false);
+            }
+        }
+
+        fSamplers.push(gpu->resourceProvider().findOrCreateCompatibleSampler(params,
+                                                          texture->texturePriv().maxMipMapLevel()));
 
         const GrVkImage::Resource* textureResource = texture->resource();
         textureResource->ref();