commit 5c6ac64516bb56bbdb5d7aedee1a348acc16e29b
author Brian Salomon <bsalomon@google.com> Tue Dec 19 11:09:32 2017 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Tue Dec 19 20:23:06 2017 +0000
tree b712f1e75a1d2f6cfc1c1d7a5453982787a829cf
parent 394197d064d976675a7952857ed5ee98e0c9edca

Revert "Revert "move homogenous with stride to matrixpriv""

This reverts commit de71572f650005e36d4fc2fe95fb5677a25ae4f6.

Revert "Revert "Transform vertices for distance field glyphs on CPU.""

This reverts commit f226e66d75374e370f3ae2c6895bc689670e9e18.

Change-Id: I2545afae3beb1d6b14bba056853ed826ae7a4679
Reviewed-on: https://skia-review.googlesource.com/86603
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

src/gpu/text/GrAtlasTextBlob.cpp

diff --git a/src/gpu/text/GrAtlasTextBlob.cpp b/src/gpu/text/GrAtlasTextBlob.cpp
index 0b25a34..02f3ab0 100644
--- a/src/gpu/text/GrAtlasTextBlob.cpp
+++ b/src/gpu/text/GrAtlasTextBlob.cpp
@@ -96,7 +96,13 @@
 
     run.fInitialized = true;
 
-    size_t vertexStride = GetVertexStride(format);
+    bool hasW = subRun->hasWCoord();
+    // DF glyphs drawn in perspective must always have a w coord.
+    SkASSERT(hasW || !subRun->drawAsDistanceFields() || !fInitialViewMatrix.hasPerspective());
+    // Non-DF glyphs should never have a w coord.
+    SkASSERT(!hasW || subRun->drawAsDistanceFields());
+
+    size_t vertexStride = GetVertexStride(format, hasW);
 
     subRun->setMaskFormat(format);
 
@@ -105,53 +111,29 @@
 
     intptr_t vertex = reinterpret_cast<intptr_t>(this->fVertices + subRun->vertexEndIndex());
 
-    if (kARGB_GrMaskFormat != glyph->fMaskFormat) {
-        // V0
-        SkPoint* position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fLeft, positions.fTop);
-        SkColor* colorPtr = reinterpret_cast<SkColor*>(vertex + sizeof(SkPoint));
-        *colorPtr = color;
-        vertex += vertexStride;
+    // We always write the third position component used by SDFs. If it is unused it gets
+    // overwritten. Similarly, we always write the color and the blob will later overwrite it
+    // with texture coords if it is unused.
+    size_t colorOffset = hasW ? sizeof(SkPoint3) : sizeof(SkPoint);
+    // V0
+    *reinterpret_cast<SkPoint3*>(vertex) = {positions.fLeft, positions.fTop, 1.f};
+    *reinterpret_cast<GrColor*>(vertex + colorOffset) = color;
+    vertex += vertexStride;
 
-        // V1
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fLeft, positions.fBottom);
-        colorPtr = reinterpret_cast<SkColor*>(vertex + sizeof(SkPoint));
-        *colorPtr = color;
-        vertex += vertexStride;
+    // V1
+    *reinterpret_cast<SkPoint3*>(vertex) = {positions.fLeft, positions.fBottom, 1.f};
+    *reinterpret_cast<GrColor*>(vertex + colorOffset) = color;
+    vertex += vertexStride;
 
-        // V2
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fRight, positions.fTop);
-        colorPtr = reinterpret_cast<SkColor*>(vertex + sizeof(SkPoint));
-        *colorPtr = color;
-        vertex += vertexStride;
+    // V2
+    *reinterpret_cast<SkPoint3*>(vertex) = {positions.fRight, positions.fTop, 1.f};
+    *reinterpret_cast<GrColor*>(vertex + colorOffset) = color;
+    vertex += vertexStride;
 
-        // V3
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fRight, positions.fBottom);
-        colorPtr = reinterpret_cast<SkColor*>(vertex + sizeof(SkPoint));
-        *colorPtr = color;
-    } else {
-        // V0
-        SkPoint* position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fLeft, positions.fTop);
-        vertex += vertexStride;
+    // V3
+    *reinterpret_cast<SkPoint3*>(vertex) = {positions.fRight, positions.fBottom, 1.f};
+    *reinterpret_cast<GrColor*>(vertex + colorOffset) = color;
 
-        // V1
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fLeft, positions.fBottom);
-        vertex += vertexStride;
-
-        // V2
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fRight, positions.fTop);
-        vertex += vertexStride;
-
-        // V3
-        position = reinterpret_cast<SkPoint*>(vertex);
-        position->set(positions.fRight, positions.fBottom);
-    }
     subRun->appendVertices(vertexStride);
     fGlyphs[subRun->glyphEndIndex()] = glyph;
     subRun->glyphAppended();
@@ -185,6 +167,7 @@
         return true;
     }
 
+    /** This could be relaxed for blobs with only distance field glyphs. */
     if (fInitialViewMatrix.hasPerspective() && !fInitialViewMatrix.cheapEqualTo(viewMatrix)) {
         return true;
     }