Add stroke support to polygonal shape rendering
bug:4419017
bug:7230005
- Adds support for stroke/strokeAndFill for shapes without joins
- Fixes path-polygonization threshold calculation
- Fixes rendering offset (now only used for points)
- Several formatting fixes
Change-Id: If72473dc881e45752e2ec212d0dcd1e3f97979ea
diff --git a/libs/hwui/PathRenderer.cpp b/libs/hwui/PathRenderer.cpp
index d222009..6893f9d 100644
--- a/libs/hwui/PathRenderer.cpp
+++ b/libs/hwui/PathRenderer.cpp
@@ -21,6 +21,7 @@
#define VERTEX_DEBUG 0
#include <SkPath.h>
+#include <SkPaint.h>
#include <stdlib.h>
#include <stdint.h>
@@ -39,10 +40,16 @@
#define THRESHOLD 0.5f
-void PathRenderer::computeInverseScales(const mat4 *transform,
- float &inverseScaleX, float& inverseScaleY) {
- inverseScaleX = 1.0f;
- inverseScaleY = 1.0f;
+SkRect PathRenderer::computePathBounds(const SkPath& path, const SkPaint* paint) {
+ SkRect bounds = path.getBounds();
+ if (paint->getStyle() != SkPaint::kFill_Style) {
+ float outset = paint->getStrokeWidth() * 0.5f;
+ bounds.outset(outset, outset);
+ }
+ return bounds;
+}
+
+void computeInverseScales(const mat4 *transform, float &inverseScaleX, float& inverseScaleY) {
if (CC_UNLIKELY(!transform->isPureTranslate())) {
float m00 = transform->data[Matrix4::kScaleX];
float m01 = transform->data[Matrix4::kSkewY];
@@ -50,127 +57,275 @@
float m11 = transform->data[Matrix4::kScaleY];
float scaleX = sqrt(m00 * m00 + m01 * m01);
float scaleY = sqrt(m10 * m10 + m11 * m11);
- inverseScaleX = (scaleX != 0) ? (inverseScaleX / scaleX) : 0;
- inverseScaleY = (scaleY != 0) ? (inverseScaleY / scaleY) : 0;
+ inverseScaleX = (scaleX != 0) ? (1.0f / scaleX) : 0;
+ inverseScaleY = (scaleY != 0) ? (1.0f / scaleY) : 0;
+ } else {
+ inverseScaleX = 1.0f;
+ inverseScaleY = 1.0f;
}
}
-void PathRenderer::convexPathFillVertices(const SkPath &path, const mat4 *transform,
- VertexBuffer &vertexBuffer, bool isAA) {
- ATRACE_CALL();
- float inverseScaleX;
- float inverseScaleY;
- computeInverseScales(transform, inverseScaleX, inverseScaleY);
+inline void copyVertex(Vertex* destPtr, const Vertex* srcPtr)
+{
+ Vertex::set(destPtr, srcPtr->position[0], srcPtr->position[1]);
+}
- Vector<Vertex> tempVertices;
- float thresholdx = THRESHOLD * inverseScaleX;
- float thresholdy = THRESHOLD * inverseScaleY;
- convexPathVertices(path,
- thresholdx * thresholdx,
- thresholdy * thresholdy,
- tempVertices);
+inline void copyAlphaVertex(AlphaVertex* destPtr, const AlphaVertex* srcPtr)
+{
+ AlphaVertex::set(destPtr, srcPtr->position[0], srcPtr->position[1], srcPtr->alpha);
+}
-#if VERTEX_DEBUG
- for (unsigned int i = 0; i < tempVertices.size(); i++) {
- ALOGD("orig path: point at %f %f",
- tempVertices[i].position[0],
- tempVertices[i].position[1]);
- }
-#endif
+void getFillVerticesFromPerimeter(const Vector<Vertex>& perimeter, VertexBuffer& vertexBuffer) {
+ Vertex* buffer = vertexBuffer.alloc<Vertex>(perimeter.size());
+
int currentIndex = 0;
- if (!isAA) {
- Vertex* buffer = vertexBuffer.alloc<Vertex>(tempVertices.size());
-
- // zig zag between all previous points on the inside of the hull to create a
- // triangle strip that fills the hull
- int srcAindex = 0;
- int srcBindex = tempVertices.size() - 1;
- while (srcAindex <= srcBindex) {
- Vertex::set(&buffer[currentIndex++],
- tempVertices.editArray()[srcAindex].position[0],
- tempVertices.editArray()[srcAindex].position[1]);
- if (srcAindex == srcBindex) break;
- Vertex::set(&buffer[currentIndex++],
- tempVertices.editArray()[srcBindex].position[0],
- tempVertices.editArray()[srcBindex].position[1]);
- srcAindex++;
- srcBindex--;
- }
- return;
+ // zig zag between all previous points on the inside of the hull to create a
+ // triangle strip that fills the hull
+ int srcAindex = 0;
+ int srcBindex = perimeter.size() - 1;
+ while (srcAindex <= srcBindex) {
+ copyVertex(&buffer[currentIndex++], &perimeter[srcAindex]);
+ if (srcAindex == srcBindex) break;
+ copyVertex(&buffer[currentIndex++], &perimeter[srcBindex]);
+ srcAindex++;
+ srcBindex--;
}
- AlphaVertex* buffer = vertexBuffer.alloc<AlphaVertex>(tempVertices.size() * 3 + 2);
+}
+
+void getStrokeVerticesFromPerimeter(const Vector<Vertex>& perimeter, float halfStrokeWidth,
+ VertexBuffer& vertexBuffer, float inverseScaleX, float inverseScaleY) {
+ Vertex* buffer = vertexBuffer.alloc<Vertex>(perimeter.size() * 2 + 2);
+
+ int currentIndex = 0;
+ const Vertex* last = &(perimeter[perimeter.size() - 1]);
+ const Vertex* current = &(perimeter[0]);
+ vec2 lastNormal(current->position[1] - last->position[1],
+ last->position[0] - current->position[0]);
+ lastNormal.normalize();
+ for (unsigned int i = 0; i < perimeter.size(); i++) {
+ const Vertex* next = &(perimeter[i + 1 >= perimeter.size() ? 0 : i + 1]);
+ vec2 nextNormal(next->position[1] - current->position[1],
+ current->position[0] - next->position[0]);
+ nextNormal.normalize();
+
+ // offset each point by its normal, out and in, by appropriate stroke offset
+ vec2 totalOffset = (lastNormal + nextNormal);
+ totalOffset.normalize();
+ if (halfStrokeWidth == 0.0f) {
+ // hairline - compensate for scale
+ totalOffset.x *= 0.5f * inverseScaleX;
+ totalOffset.y *= 0.5f * inverseScaleY;
+ } else {
+ totalOffset *= halfStrokeWidth;
+ }
+
+ Vertex::set(&buffer[currentIndex++],
+ current->position[0] + totalOffset.x,
+ current->position[1] + totalOffset.y);
+
+ Vertex::set(&buffer[currentIndex++],
+ current->position[0] - totalOffset.x,
+ current->position[1] - totalOffset.y);
+
+ last = current;
+ current = next;
+ lastNormal = nextNormal;
+ }
+
+ // wrap around to beginning
+ copyVertex(&buffer[currentIndex++], &buffer[0]);
+ copyVertex(&buffer[currentIndex++], &buffer[1]);
+}
+
+void getFillVerticesFromPerimeterAA(const Vector<Vertex>& perimeter, VertexBuffer& vertexBuffer,
+ float inverseScaleX, float inverseScaleY) {
+ AlphaVertex* buffer = vertexBuffer.alloc<AlphaVertex>(perimeter.size() * 3 + 2);
// generate alpha points - fill Alpha vertex gaps in between each point with
// alpha 0 vertex, offset by a scaled normal.
- Vertex* last = &(tempVertices.editArray()[tempVertices.size()-1]);
-
- for (unsigned int i = 0; i<tempVertices.size(); i++) {
- Vertex* current = &(tempVertices.editArray()[i]);
- Vertex* next = &(tempVertices.editArray()[i + 1 >= tempVertices.size() ? 0 : i + 1]);
-
- vec2 lastNormal(current->position[1] - last->position[1],
- last->position[0] - current->position[0]);
- lastNormal.normalize();
+ int currentIndex = 0;
+ const Vertex* last = &(perimeter[perimeter.size() - 1]);
+ const Vertex* current = &(perimeter[0]);
+ vec2 lastNormal(current->position[1] - last->position[1],
+ last->position[0] - current->position[0]);
+ lastNormal.normalize();
+ for (unsigned int i = 0; i < perimeter.size(); i++) {
+ const Vertex* next = &(perimeter[i + 1 >= perimeter.size() ? 0 : i + 1]);
vec2 nextNormal(next->position[1] - current->position[1],
- current->position[0] - next->position[0]);
+ current->position[0] - next->position[0]);
nextNormal.normalize();
// AA point offset from original point is that point's normal, such that
// each side is offset by .5 pixels
- vec2 totalOffset = (lastNormal + nextNormal) / (2 * (1 + lastNormal.dot(nextNormal)));
- totalOffset.x *= inverseScaleX;
- totalOffset.y *= inverseScaleY;
+ vec2 totalOffset = (lastNormal + nextNormal);
+ totalOffset.normalize();
+ totalOffset.x *= inverseScaleX * 0.5f;
+ totalOffset.y *= inverseScaleY * 0.5f;
AlphaVertex::set(&buffer[currentIndex++],
- current->position[0] + totalOffset.x,
- current->position[1] + totalOffset.y,
- 0.0f);
+ current->position[0] + totalOffset.x,
+ current->position[1] + totalOffset.y,
+ 0.0f);
AlphaVertex::set(&buffer[currentIndex++],
- current->position[0] - totalOffset.x,
- current->position[1] - totalOffset.y,
- 1.0f);
+ current->position[0] - totalOffset.x,
+ current->position[1] - totalOffset.y,
+ 1.0f);
+
last = current;
+ current = next;
+ lastNormal = nextNormal;
}
// wrap around to beginning
- AlphaVertex::set(&buffer[currentIndex++],
- buffer[0].position[0],
- buffer[0].position[1], 0.0f);
- AlphaVertex::set(&buffer[currentIndex++],
- buffer[1].position[0],
- buffer[1].position[1], 1.0f);
+ copyAlphaVertex(&buffer[currentIndex++], &buffer[0]);
+ copyAlphaVertex(&buffer[currentIndex++], &buffer[1]);
// zig zag between all previous points on the inside of the hull to create a
// triangle strip that fills the hull, repeating the first inner point to
// create degenerate tris to start inside path
int srcAindex = 0;
- int srcBindex = tempVertices.size() - 1;
+ int srcBindex = perimeter.size() - 1;
while (srcAindex <= srcBindex) {
- AlphaVertex::set(&buffer[currentIndex++],
- buffer[srcAindex * 2 + 1].position[0],
- buffer[srcAindex * 2 + 1].position[1],
- 1.0f);
+ copyAlphaVertex(&buffer[currentIndex++], &buffer[srcAindex * 2 + 1]);
if (srcAindex == srcBindex) break;
- AlphaVertex::set(&buffer[currentIndex++],
- buffer[srcBindex * 2 + 1].position[0],
- buffer[srcBindex * 2 + 1].position[1],
- 1.0f);
+ copyAlphaVertex(&buffer[currentIndex++], &buffer[srcBindex * 2 + 1]);
srcAindex++;
srcBindex--;
}
#if VERTEX_DEBUG
- for (unsigned int i = 0; i < vertexBuffer.mSize; i++) {
- ALOGD("point at %f %f",
- buffer[i].position[0],
- buffer[i].position[1]);
+ for (unsigned int i = 0; i < vertexBuffer.getSize(); i++) {
+ ALOGD("point at %f %f", buffer[i].position[0], buffer[i].position[1]);
}
#endif
}
+void getStrokeVerticesFromPerimeterAA(const Vector<Vertex>& perimeter, float halfStrokeWidth,
+ VertexBuffer& vertexBuffer, float inverseScaleX, float inverseScaleY) {
+ AlphaVertex* buffer = vertexBuffer.alloc<AlphaVertex>(6 * perimeter.size() + 8);
-void PathRenderer::convexPathVertices(const SkPath &path, float thresholdx, float thresholdy,
- Vector<Vertex> &outputVertices) {
+ int offset = 2 * perimeter.size() + 3;
+ int currentAAOuterIndex = 0;
+ int currentStrokeIndex = offset;
+ int currentAAInnerIndex = offset * 2;
+
+ const Vertex* last = &(perimeter[perimeter.size() - 1]);
+ const Vertex* current = &(perimeter[0]);
+ vec2 lastNormal(current->position[1] - last->position[1],
+ last->position[0] - current->position[0]);
+ lastNormal.normalize();
+ for (unsigned int i = 0; i < perimeter.size(); i++) {
+ const Vertex* next = &(perimeter[i + 1 >= perimeter.size() ? 0 : i + 1]);
+ vec2 nextNormal(next->position[1] - current->position[1],
+ current->position[0] - next->position[0]);
+ nextNormal.normalize();
+
+ vec2 pointNormal = (lastNormal + nextNormal);
+ pointNormal.normalize();
+ vec2 AAOffset = pointNormal * 0.5f;
+ AAOffset.x *= inverseScaleX;
+ AAOffset.y *= inverseScaleY;
+
+ vec2 innerOffset = pointNormal;
+ if (halfStrokeWidth == 0.0f) {
+ // hairline! - compensate for scale
+ innerOffset.x *= 0.5f * inverseScaleX;
+ innerOffset.y *= 0.5f * inverseScaleY;
+ } else {
+ innerOffset *= halfStrokeWidth;
+ }
+ vec2 outerOffset = innerOffset + AAOffset;
+ innerOffset -= AAOffset;
+
+ AlphaVertex::set(&buffer[currentAAOuterIndex++],
+ current->position[0] + outerOffset.x,
+ current->position[1] + outerOffset.y,
+ 0.0f);
+ AlphaVertex::set(&buffer[currentAAOuterIndex++],
+ current->position[0] + innerOffset.x,
+ current->position[1] + innerOffset.y,
+ 1.0f);
+
+ AlphaVertex::set(&buffer[currentStrokeIndex++],
+ current->position[0] + innerOffset.x,
+ current->position[1] + innerOffset.y,
+ 1.0f);
+ AlphaVertex::set(&buffer[currentStrokeIndex++],
+ current->position[0] - innerOffset.x,
+ current->position[1] - innerOffset.y,
+ 1.0f);
+
+ AlphaVertex::set(&buffer[currentAAInnerIndex++],
+ current->position[0] - innerOffset.x,
+ current->position[1] - innerOffset.y,
+ 1.0f);
+ AlphaVertex::set(&buffer[currentAAInnerIndex++],
+ current->position[0] - outerOffset.x,
+ current->position[1] - outerOffset.y,
+ 0.0f);
+
+ // TODO: current = next, copy last normal instead of recalculate
+ last = current;
+ current = next;
+ lastNormal = nextNormal;
+ }
+
+ // wrap each strip around to beginning, creating degenerate tris to bridge strips
+ copyAlphaVertex(&buffer[currentAAOuterIndex++], &buffer[0]);
+ copyAlphaVertex(&buffer[currentAAOuterIndex++], &buffer[1]);
+ copyAlphaVertex(&buffer[currentAAOuterIndex++], &buffer[1]);
+
+ copyAlphaVertex(&buffer[currentStrokeIndex++], &buffer[offset]);
+ copyAlphaVertex(&buffer[currentStrokeIndex++], &buffer[offset + 1]);
+ copyAlphaVertex(&buffer[currentStrokeIndex++], &buffer[offset + 1]);
+
+ copyAlphaVertex(&buffer[currentAAInnerIndex++], &buffer[2 * offset]);
+ copyAlphaVertex(&buffer[currentAAInnerIndex++], &buffer[2 * offset + 1]);
+ // don't need to create last degenerate tri
+}
+
+void PathRenderer::convexPathVertices(const SkPath &path, const SkPaint* paint,
+ const mat4 *transform, VertexBuffer& vertexBuffer) {
+ ATRACE_CALL();
+
+ SkPaint::Style style = paint->getStyle();
+ bool isAA = paint->isAntiAlias();
+
+ float inverseScaleX, inverseScaleY;
+ computeInverseScales(transform, inverseScaleX, inverseScaleY);
+
+ Vector<Vertex> tempVertices;
+ convexPathPerimeterVertices(path, inverseScaleX * inverseScaleX, inverseScaleY * inverseScaleY,
+ tempVertices);
+
+#if VERTEX_DEBUG
+ for (unsigned int i = 0; i < tempVertices.size(); i++) {
+ ALOGD("orig path: point at %f %f", tempVertices[i].position[0], tempVertices[i].position[1]);
+ }
+#endif
+
+ if (style == SkPaint::kStroke_Style) {
+ float halfStrokeWidth = paint->getStrokeWidth() * 0.5f;
+ if (!isAA) {
+ getStrokeVerticesFromPerimeter(tempVertices, halfStrokeWidth, vertexBuffer,
+ inverseScaleX, inverseScaleY);
+ } else {
+ getStrokeVerticesFromPerimeterAA(tempVertices, halfStrokeWidth, vertexBuffer,
+ inverseScaleX, inverseScaleY);
+ }
+ } else {
+ // For kStrokeAndFill style, the path should be adjusted externally, as it will be treated as a fill here.
+ if (!isAA) {
+ getFillVerticesFromPerimeter(tempVertices, vertexBuffer);
+ } else {
+ getFillVerticesFromPerimeterAA(tempVertices, vertexBuffer, inverseScaleX, inverseScaleY);
+ }
+ }
+}
+
+
+void PathRenderer::convexPathPerimeterVertices(const SkPath& path,
+ float sqrInvScaleX, float sqrInvScaleY, Vector<Vertex>& outputVertices) {
ATRACE_CALL();
SkPath::Iter iter(path, true);
@@ -189,31 +344,30 @@
break;
case SkPath::kLine_Verb:
ALOGV("kLine_Verb %f %f -> %f %f",
- pts[0].x(), pts[0].y(),
- pts[1].x(), pts[1].y());
+ pts[0].x(), pts[0].y(),
+ pts[1].x(), pts[1].y());
// TODO: make this not yuck
outputVertices.push();
- newVertex = &(outputVertices.editArray()[outputVertices.size()-1]);
+ newVertex = &(outputVertices.editArray()[outputVertices.size() - 1]);
Vertex::set(newVertex, pts[1].x(), pts[1].y());
break;
case SkPath::kQuad_Verb:
ALOGV("kQuad_Verb");
recursiveQuadraticBezierVertices(
- pts[0].x(), pts[0].y(),
- pts[2].x(), pts[2].y(),
- pts[1].x(), pts[1].y(),
- thresholdx, thresholdy,
- outputVertices);
+ pts[0].x(), pts[0].y(),
+ pts[2].x(), pts[2].y(),
+ pts[1].x(), pts[1].y(),
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
break;
case SkPath::kCubic_Verb:
ALOGV("kCubic_Verb");
recursiveCubicBezierVertices(
- pts[0].x(), pts[0].y(),
- pts[1].x(), pts[1].y(),
- pts[3].x(), pts[3].y(),
- pts[2].x(), pts[2].y(),
- thresholdx, thresholdy, outputVertices);
+ pts[0].x(), pts[0].y(),
+ pts[1].x(), pts[1].y(),
+ pts[3].x(), pts[3].y(),
+ pts[2].x(), pts[2].y(),
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
break;
default:
break;
@@ -224,18 +378,20 @@
void PathRenderer::recursiveCubicBezierVertices(
float p1x, float p1y, float c1x, float c1y,
float p2x, float p2y, float c2x, float c2y,
- float thresholdx, float thresholdy, Vector<Vertex> &outputVertices) {
+ float sqrInvScaleX, float sqrInvScaleY, Vector<Vertex>& outputVertices) {
float dx = p2x - p1x;
float dy = p2y - p1y;
float d1 = fabs((c1x - p2x) * dy - (c1y - p2y) * dx);
float d2 = fabs((c2x - p2x) * dy - (c2y - p2y) * dx);
float d = d1 + d2;
- if (d * d < (thresholdx * (dx * dx) + thresholdy * (dy * dy))) {
+ // multiplying by sqrInvScaleY/X equivalent to multiplying in dimensional scale factors
+
+ if (d * d < THRESHOLD * THRESHOLD * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
// below thresh, draw line by adding endpoint
// TODO: make this not yuck
outputVertices.push();
- Vertex* newVertex = &(outputVertices.editArray()[outputVertices.size()-1]);
+ Vertex* newVertex = &(outputVertices.editArray()[outputVertices.size() - 1]);
Vertex::set(newVertex, p2x, p2y);
} else {
float p1c1x = (p1x + c1x) * 0.5f;
@@ -258,13 +414,11 @@
recursiveCubicBezierVertices(
p1x, p1y, p1c1x, p1c1y,
mx, my, p1c1c2x, p1c1c2y,
- thresholdx, thresholdy,
- outputVertices);
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
recursiveCubicBezierVertices(
mx, my, p2c1c2x, p2c1c2y,
p2x, p2y, p2c2x, p2c2y,
- thresholdx, thresholdy,
- outputVertices);
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
}
}
@@ -272,16 +426,16 @@
float ax, float ay,
float bx, float by,
float cx, float cy,
- float thresholdx, float thresholdy, Vector<Vertex> &outputVertices) {
+ float sqrInvScaleX, float sqrInvScaleY, Vector<Vertex>& outputVertices) {
float dx = bx - ax;
float dy = by - ay;
float d = (cx - bx) * dy - (cy - by) * dx;
- if (d * d < (thresholdx * (dx * dx) + thresholdy * (dy * dy))) {
+ if (d * d < THRESHOLD * THRESHOLD * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
// below thresh, draw line by adding endpoint
// TODO: make this not yuck
outputVertices.push();
- Vertex* newVertex = &(outputVertices.editArray()[outputVertices.size()-1]);
+ Vertex* newVertex = &(outputVertices.editArray()[outputVertices.size() - 1]);
Vertex::set(newVertex, bx, by);
} else {
float acx = (ax + cx) * 0.5f;
@@ -294,9 +448,9 @@
float my = (acy + bcy) * 0.5f;
recursiveQuadraticBezierVertices(ax, ay, mx, my, acx, acy,
- thresholdx, thresholdy, outputVertices);
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
recursiveQuadraticBezierVertices(mx, my, bx, by, bcx, bcy,
- thresholdx, thresholdy, outputVertices);
+ sqrInvScaleX, sqrInvScaleY, outputVertices);
}
}