Handle different x, y scales in drawLines AA path

bug:7114630

Fixes different x, y scales, and fixes boundaryWidthProportion to be from
center, not edge.

Also adds drawLine tests that previously drew blurry.

Change-Id: I2b648a60361ad3931eac67647b9b27909525ee1e

1 files changed, 5 insertions, 5 deletions

diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index b66c898..77a4f13 100644
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -1978,6 +1978,10 @@ status_t OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
 
         // Find the normal to the line
         vec2 n = (b - a).copyNormalized() * halfStrokeWidth;
+        float x = n.x;
+        n.x = -n.y;
+        n.y = x;
+
         if (isHairLine) {
             if (isAA) {
                 float wideningFactor;
@@ -2002,14 +2006,10 @@ status_t OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
 
             float extendedNLength = extendedN.length();
             // We need to set this value on the shader prior to drawing
-            boundaryWidthProportion = extendedNLength / (halfStrokeWidth + extendedNLength);
+            boundaryWidthProportion = .5 - extendedNLength / (halfStrokeWidth + extendedNLength);
             n += extendedN;
         }
 
-        float x = n.x;
-        n.x = -n.y;
-        n.y = x;
-
         // aa lines expand the endpoint vertices to encompass the AA boundary
         if (isAA) {
             vec2 abVector = (b - a);