Fix up and clarify use of maxMipLevel in Vulkan

Bug: skia:
Change-Id: I5b31e0c74be8f650e97c448b1029a2277dfee978
Reviewed-on: https://skia-review.googlesource.com/41844
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>

5 files changed, 15 insertions, 14 deletions

diff --git a/src/gpu/vk/GrVkResourceProvider.cpp b/src/gpu/vk/GrVkResourceProvider.cpp
index 0f4b2a9f34..cfce75f1ca 100644
--- a/src/gpu/vk/GrVkResourceProvider.cpp
+++ b/src/gpu/vk/GrVkResourceProvider.cpp
@@ -166,10 +166,10 @@ GrVkDescriptorPool* GrVkResourceProvider::findOrCreateCompatibleDescriptorPool(
 }
 
 GrVkSampler* GrVkResourceProvider::findOrCreateCompatibleSampler(const GrSamplerParams& params,
-                                                                 uint32_t mipLevels) {
-    GrVkSampler* sampler = fSamplers.find(GrVkSampler::GenerateKey(params, mipLevels));
+                                                                 uint32_t maxMipLevel) {
+    GrVkSampler* sampler = fSamplers.find(GrVkSampler::GenerateKey(params, maxMipLevel));
     if (!sampler) {
-        sampler = GrVkSampler::Create(fGpu, params, mipLevels);
+        sampler = GrVkSampler::Create(fGpu, params, maxMipLevel);
         fSamplers.add(sampler);
     }
     SkASSERT(sampler);
diff --git a/src/gpu/vk/GrVkResourceProvider.h b/src/gpu/vk/GrVkResourceProvider.h
index 5940681e8c..ba11c8db52 100644
--- a/src/gpu/vk/GrVkResourceProvider.h
+++ b/src/gpu/vk/GrVkResourceProvider.h
@@ -98,7 +98,7 @@ public:
 
     // Finds or creates a compatible GrVkSampler based on the GrSamplerParams.
     // The refcount is incremented and a pointer returned.
-    GrVkSampler* findOrCreateCompatibleSampler(const GrSamplerParams&, uint32_t mipLevels);
+    GrVkSampler* findOrCreateCompatibleSampler(const GrSamplerParams&, uint32_t maxMipLevel);
 
     sk_sp<GrVkPipelineState> findOrCreateCompatiblePipelineState(const GrPipeline&,
                                                                  const GrPrimitiveProcessor&,
diff --git a/src/gpu/vk/GrVkSampler.cpp b/src/gpu/vk/GrVkSampler.cpp
index 39016344c7..740c14b4de 100644
--- a/src/gpu/vk/GrVkSampler.cpp
+++ b/src/gpu/vk/GrVkSampler.cpp
@@ -23,7 +23,7 @@ static inline VkSamplerAddressMode tile_to_vk_sampler_address(SkShader::TileMode
 }
 
 GrVkSampler* GrVkSampler::Create(const GrVkGpu* gpu, const GrSamplerParams& params,
-                                 uint32_t mipLevels) {
+                                 uint32_t maxMipLevel) {
     static VkFilter vkMinFilterModes[] = {
         VK_FILTER_NEAREST,
         VK_FILTER_LINEAR,
@@ -57,8 +57,8 @@ GrVkSampler* GrVkSampler::Create(const GrVkGpu* gpu, const GrSamplerParams& para
     // level mip). If the filters weren't the same we could set min = 0 and max = 0.25 to force
     // the minFilter on mip level 0.
     createInfo.minLod = 0.0f;
-    bool useMipMaps = GrSamplerParams::kMipMap_FilterMode == params.filterMode() && mipLevels > 1;
-    createInfo.maxLod = !useMipMaps ? 0.0f : (float)(mipLevels);
+    bool useMipMaps = GrSamplerParams::kMipMap_FilterMode == params.filterMode() && maxMipLevel > 0;
+    createInfo.maxLod = !useMipMaps ? 0.0f : (float)(maxMipLevel);
     createInfo.borderColor = VK_BORDER_COLOR_FLOAT_TRANSPARENT_BLACK;
     createInfo.unnormalizedCoordinates = VK_FALSE;
 
@@ -68,7 +68,7 @@ GrVkSampler* GrVkSampler::Create(const GrVkGpu* gpu, const GrSamplerParams& para
                                                           nullptr,
                                                           &sampler));
 
-    return new GrVkSampler(sampler, GenerateKey(params, mipLevels));
+    return new GrVkSampler(sampler, GenerateKey(params, maxMipLevel));
 }
 
 void GrVkSampler::freeGPUData(const GrVkGpu* gpu) const {
@@ -76,7 +76,7 @@ void GrVkSampler::freeGPUData(const GrVkGpu* gpu) const {
     GR_VK_CALL(gpu->vkInterface(), DestroySampler(gpu->device(), fSampler, nullptr));
 }
 
-uint16_t GrVkSampler::GenerateKey(const GrSamplerParams& params, uint32_t mipLevels) {
+uint16_t GrVkSampler::GenerateKey(const GrSamplerParams& params, uint32_t maxMipLevel) {
     const int kTileModeXShift = 2;
     const int kTileModeYShift = 4;
     const int kMipLevelShift = 6;
@@ -89,8 +89,8 @@ uint16_t GrVkSampler::GenerateKey(const GrSamplerParams& params, uint32_t mipLev
     GR_STATIC_ASSERT(SkShader::kTileModeCount <= 4);
     key |= (params.getTileModeY() << kTileModeYShift);
 
-    SkASSERT(mipLevels < 1024);
-    key |= (mipLevels << kMipLevelShift);
+    SkASSERT(maxMipLevel < 1024);
+    key |= (maxMipLevel << kMipLevelShift);
 
     return key;
 }
diff --git a/src/gpu/vk/GrVkSampler.h b/src/gpu/vk/GrVkSampler.h
index 963060239f..a413ea826a 100644
--- a/src/gpu/vk/GrVkSampler.h
+++ b/src/gpu/vk/GrVkSampler.h
@@ -18,12 +18,12 @@ class GrVkGpu;
 
 class GrVkSampler : public GrVkResource {
 public:
-    static GrVkSampler* Create(const GrVkGpu* gpu, const GrSamplerParams&, uint32_t mipLevels);
+    static GrVkSampler* Create(const GrVkGpu* gpu, const GrSamplerParams&, uint32_t maxMipLevel);
 
     VkSampler sampler() const { return fSampler; }
 
     // Helpers for hashing GrVkSampler
-    static uint16_t GenerateKey(const GrSamplerParams&, uint32_t mipLevels);
+    static uint16_t GenerateKey(const GrSamplerParams&, uint32_t maxMipLevel);
 
     static const uint16_t& GetKey(const GrVkSampler& sampler) { return sampler.fKey; }
     static uint32_t Hash(const uint16_t& key) { return key; }
diff --git a/src/gpu/vk/GrVkTexture.cpp b/src/gpu/vk/GrVkTexture.cpp
index 90de6be9a7..ce1d4875d6 100644
--- a/src/gpu/vk/GrVkTexture.cpp
+++ b/src/gpu/vk/GrVkTexture.cpp
@@ -239,7 +239,8 @@ bool GrVkTexture::reallocForMipmap(GrVkGpu* gpu, uint32_t mipLevels) {
     this->setNewResource(info.fImage, info.fAlloc, info.fImageTiling);
     fTextureView = textureView;
     fInfo = info;
-    this->texturePriv().setMaxMipMapLevel(mipLevels);
+    // SetMaxMipMapLevel stores the max level not the number of levels
+    this->texturePriv().setMaxMipMapLevel(mipLevels-1);
 
     return true;
 }