Update vulkan format features in caps.

src/gpu/vk/GrVkSampler.cpp

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #include "GrVkSampler.h"
 
 #include "GrTextureAccess.h"
@@ skipping 34 matching lines @@
     createInfo.minFilter = vkMinFilterModes[params.filterMode()];
     createInfo.mipmapMode = VK_SAMPLER_MIPMAP_MODE_NEAREST;
     createInfo.addressModeU = tile_to_vk_sampler_address(params.getTileModeX());
     createInfo.addressModeV = tile_to_vk_sampler_address(params.getTileModeY());
     createInfo.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE; // Shouldn't matter
     createInfo.mipLodBias = 0.0f;
     createInfo.anisotropyEnable = VK_FALSE;
     createInfo.maxAnisotropy = 1.0f;
     createInfo.compareEnable = VK_FALSE;
     createInfo.compareOp = VK_COMPARE_OP_NEVER;
+    // Vulkan doesn't have a direct mapping of GL's nearest or linear filters for minFilter since
+    // there is always a mipmapMode. To get the same effect as GL we can set minLod = maxLod = 0.0.
+    // This works since our min and mag filters are the same (this forces us to use mag on the 0
+    // 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;
     createInfo.maxLod = 0.0f;
     createInfo.borderColor = VK_BORDER_COLOR_FLOAT_TRANSPARENT_BLACK;
     createInfo.unnormalizedCoordinates = VK_FALSE;
 
     VkSampler sampler;
     GR_VK_CALL_ERRCHECK(gpu->vkInterface(), CreateSampler(gpu->device(),
                                                           &createInfo,
                                                           nullptr,
                                                           &sampler));
@@ skipping 11 matching lines @@
     uint8_t key = params.filterMode();
 
     SkASSERT(params.filterMode() <= 3);
     key |= (params.getTileModeX() << 2);
 
     GR_STATIC_ASSERT(SkShader::kTileModeCount <= 4);
     key |= (params.getTileModeY() << 4);
 
     return key;
 }