commit c74f45a334f0e3725c23cdd270cbcb0efac4ea75
author Romain Guy <romainguy@google.com> Tue Feb 26 19:10:14 2013 -0800
committer Romain Guy <romainguy@google.com> Wed Feb 27 15:49:57 2013 -0800
tree 1b198e8b6b7d6d4a69237116a580236836744294
parent d80806b305ce337283c24f14522cc58fea090b8c

Properly scale text

This change does not apply to drawPosText() and drawTextOnPath() yet.

Prior to this change, glyphs were always rasterized based on the
font size specified in the paint. All transforms were then applied
on the resulting texture. This creates rather ugly results when
text is scaled and/or rotated.

With this change, the font renderer will apply the current transform
matrix to the glyph before they are rasterized. This generates much
better looking results.

Change-Id: I0141b6ff18db35e1213e7a3ab9db1ecaf03d7a9c

libs/hwui/OpenGLRenderer.cpp

diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index d683c27..fb77ef6 100644
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -1657,13 +1657,13 @@
         mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
         if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
     } else {
-        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
+        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mat4::identity());
         if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
     }
 }
 
 void OpenGLRenderer::setupDrawModelViewIdentity(bool offset) {
-    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform, offset);
+    mCaches.currentProgram->set(mOrthoMatrix, mat4::identity(), *mSnapshot->transform, offset);
 }
 
 void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
@@ -1681,7 +1681,7 @@
             dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
         }
     } else {
-        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
+        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mat4::identity());
         if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
     }
 }
@@ -1716,7 +1716,7 @@
 void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
     if (mDrawModifiers.mShader) {
         mDrawModifiers.mShader->setupProgram(mCaches.currentProgram,
-                mIdentity, *mSnapshot, &mTextureUnit);
+                mat4::identity(), *mSnapshot, &mTextureUnit);
     }
 }
 
@@ -2587,7 +2587,7 @@
     }
 
     FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
-    fontRenderer.setFont(paint, *mSnapshot->transform);
+    fontRenderer.setFont(paint, mat4::identity());
 
     int alpha;
     SkXfermode::Mode mode;
@@ -2663,17 +2663,10 @@
         return DrawGlInfo::kStatusDone;
     }
 
-#if DEBUG_GLYPHS
-    ALOGD("OpenGLRenderer drawText() with FontID=%d",
-            SkTypeface::UniqueID(paint->getTypeface()));
-#endif
-
-    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
-    fontRenderer.setFont(paint, *mSnapshot->transform);
-
     const float oldX = x;
     const float oldY = y;
     const bool pureTranslate = mSnapshot->transform->isPureTranslate();
+
     if (CC_LIKELY(pureTranslate)) {
         x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
         y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
@@ -2683,16 +2676,19 @@
     SkXfermode::Mode mode;
     getAlphaAndMode(paint, &alpha, &mode);
 
+    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
+
     if (CC_UNLIKELY(mDrawModifiers.mHasShadow)) {
-        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer, alpha, mode,
-                oldX, oldY);
+        fontRenderer.setFont(paint, mat4::identity());
+        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
+                alpha, mode, oldX, oldY);
     }
 
+    fontRenderer.setFont(paint, pureTranslate ? mat4::identity() : *mSnapshot->transform);
+
     // Pick the appropriate texture filtering
-    bool linearFilter = mSnapshot->transform->changesBounds();
-    if (pureTranslate && !linearFilter) {
-        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
-    }
+    bool linearFilter = !mSnapshot->transform->isPureTranslate() ||
+            fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
 
     // The font renderer will always use texture unit 0
     mCaches.activeTexture(0);
@@ -2705,17 +2701,16 @@
     setupDrawShader();
     setupDrawBlending(true, mode);
     setupDrawProgram();
-    setupDrawModelView(x, y, x, y, pureTranslate, true);
+    setupDrawModelView(x, y, x, y, true, true);
     // See comment above; the font renderer must use texture unit 0
     // assert(mTextureUnit == 0)
     setupDrawTexture(fontRenderer.getTexture(linearFilter));
     setupDrawPureColorUniforms();
     setupDrawColorFilterUniforms();
-    setupDrawShaderUniforms(pureTranslate);
+    setupDrawShaderUniforms(true);
     setupDrawTextGammaUniforms();
 
-    const Rect* clip = pureTranslate ? mSnapshot->clipRect :
-            (mSnapshot->hasPerspectiveTransform() ? NULL : &mSnapshot->getLocalClip());
+    const Rect* clip = mSnapshot->hasPerspectiveTransform() ? NULL : mSnapshot->clipRect;
     Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
 
     const bool hasActiveLayer = hasLayer();
@@ -2732,9 +2727,6 @@
     }
 
     if (status && hasActiveLayer) {
-        if (!pureTranslate) {
-            mSnapshot->transform->mapRect(bounds);
-        }
         dirtyLayerUnchecked(bounds, getRegion());
     }
 
@@ -2750,7 +2742,7 @@
     }
 
     FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
-    fontRenderer.setFont(paint, *mSnapshot->transform);
+    fontRenderer.setFont(paint, mat4::identity());
 
     int alpha;
     SkXfermode::Mode mode;