commit 9b009bb069aa81425438d5403a1a29f2d047f77f
author Brian Salomon <bsalomon@google.com> Wed Feb 14 13:53:55 2018 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Wed Feb 14 19:58:14 2018 +0000
tree a3ff6b83971d9c1564d1de84e219a187f703ed8b
parent 95edb43251e8fcef4286c91d334c3259940a0095

Prepare sRGB encoding conversion for the removal of GrPixelConfig

Standardizes that GrGpu subclass's onRead/WritePixels never do sRGB<->linear conversion. This means that they can eventually take a color type rather than config. It also means direct callers of GrGpu::read/writePixels can never expect conversion (which in practice is no change).

Consolidate logic about whether to do sRGB<->linear encoding conversions in GrContext::read/writeSurfacePixels helpers. No change in when conversions are done (yet). This prepares this logic to operate on SkColorSpace and color type rather than config WRT the CPU data.

Bug: skia:6718
Change-Id: I346d669624861578f1bb9ea465a7ab4b549117fa
Reviewed-on: https://skia-review.googlesource.com/105286
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

src/gpu/vk/GrVkGpu.cpp

diff --git a/src/gpu/vk/GrVkGpu.cpp b/src/gpu/vk/GrVkGpu.cpp
index 35c2fcc..daa4057 100644
--- a/src/gpu/vk/GrVkGpu.cpp
+++ b/src/gpu/vk/GrVkGpu.cpp
@@ -340,6 +340,14 @@
                                    int width, int height,
                                    GrPixelConfig srcConfig, DrawPreference* drawPreference,
                                    WritePixelTempDrawInfo* tempDrawInfo) {
+    if (*drawPreference != kNoDraw_DrawPreference) {
+        // We assume the base class has only inserted a draw for sRGB reasons. So the temp surface
+        // has the config of the original src data. There is no swizzling nor src config spoofing.
+        SkASSERT(tempDrawInfo->fWriteConfig == srcConfig);
+        SkASSERT(tempDrawInfo->fTempSurfaceDesc.fConfig == srcConfig);
+        SkASSERT(tempDrawInfo->fSwizzle == GrSwizzle::RGBA());
+    }
+
     GrRenderTarget* renderTarget = dstSurface->asRenderTarget();
 
     if (dstSurface->config() == srcConfig) {
@@ -381,11 +389,6 @@
         return false;
     }
 
-    // We assume Vulkan doesn't do sRGB <-> linear conversions when reading and writing pixels.
-    if (GrPixelConfigIsSRGB(surface->config()) != GrPixelConfigIsSRGB(config)) {
-        return false;
-    }
-
     bool success = false;
     bool linearTiling = vkTex->isLinearTiled();
     if (linearTiling) {
@@ -435,11 +438,6 @@
         return false;
     }
 
-    // We assume Vulkan doesn't do sRGB <-> linear conversions when reading and writing pixels.
-    if (GrPixelConfigIsSRGB(texture->config()) != GrPixelConfigIsSRGB(config)) {
-        return false;
-    }
-
     SkDEBUGCODE(
         SkIRect subRect = SkIRect::MakeXYWH(left, top, width, height);
         SkIRect bounds = SkIRect::MakeWH(texture->width(), texture->height());
@@ -1859,29 +1857,35 @@
     *effectiveSampleCnt = rt->numStencilSamples();
 }
 
-bool GrVkGpu::onGetReadPixelsInfo(GrSurface* srcSurface, GrSurfaceOrigin srcOrigin,
-                                  int width, int height, size_t rowBytes,
-                                  GrPixelConfig readConfig, DrawPreference* drawPreference,
+bool GrVkGpu::onGetReadPixelsInfo(GrSurface* srcSurface, GrSurfaceOrigin srcOrigin, int width,
+                                  int height, size_t rowBytes, GrPixelConfig dstConfig,
+                                  DrawPreference* drawPreference,
                                   ReadPixelTempDrawInfo* tempDrawInfo) {
-    if (srcSurface->config() == readConfig) {
+    if (*drawPreference != kNoDraw_DrawPreference) {
+        // We assume the base class has only inserted a draw for sRGB reasons. So the
+        // the temp surface has the config of the dst data. There is no swizzling nor dst config.
+        // spoofing.
+        SkASSERT(tempDrawInfo->fReadConfig == dstConfig);
+        SkASSERT(tempDrawInfo->fTempSurfaceDesc.fConfig == dstConfig);
+        SkASSERT(tempDrawInfo->fSwizzle == GrSwizzle::RGBA());
+    }
+
+    if (srcSurface->config() == dstConfig) {
         return true;
     }
 
     // Any config change requires a draw
     ElevateDrawPreference(drawPreference, kRequireDraw_DrawPreference);
-    tempDrawInfo->fTempSurfaceDesc.fConfig = readConfig;
-    tempDrawInfo->fReadConfig = readConfig;
+    tempDrawInfo->fTempSurfaceDesc.fConfig = dstConfig;
+    tempDrawInfo->fReadConfig = dstConfig;
 
     return true;
 }
 
-bool GrVkGpu::onReadPixels(GrSurface* surface, GrSurfaceOrigin origin,
-                           int left, int top, int width, int height,
-                           GrPixelConfig config,
-                           void* buffer,
-                           size_t rowBytes) {
+bool GrVkGpu::onReadPixels(GrSurface* surface, GrSurfaceOrigin origin, int left, int top, int width,
+                           int height, GrPixelConfig dstConfig, void* buffer, size_t rowBytes) {
     VkFormat pixelFormat;
-    if (!GrPixelConfigToVkFormat(config, &pixelFormat)) {
+    if (!GrPixelConfigToVkFormat(dstConfig, &pixelFormat)) {
         return false;
     }
 
@@ -1916,7 +1920,7 @@
                           VK_PIPELINE_STAGE_TRANSFER_BIT,
                           false);
 
-    size_t bpp = GrBytesPerPixel(config);
+    size_t bpp = GrBytesPerPixel(dstConfig);
     size_t tightRowBytes = bpp * width;
     bool flipY = kBottomLeft_GrSurfaceOrigin == origin;