Merge "Tweak the threshold for conic path quads computation." into mnc-dev (e9d8480f) · Commits · e / os / android_frameworks_base

libs/hwui/PathTessellator.cpp

+35 −25

Original line number	Diff line number	Diff line
		@@ -56,7 +56,7 @@
		namespace android {
		namespace uirenderer {

		#define OUTLINE_REFINE_THRESHOLD_SQUARED (0.5f * 0.5f)
		#define OUTLINE_REFINE_THRESHOLD 0.5f
		#define ROUND_CAP_THRESH 0.25f
		#define PI 3.1415926535897932f
		#define MAX_DEPTH 15
		@@ -739,9 +739,10 @@ void PathTessellator::tessellatePath(const SkPath &path, const SkPaint* paint,

		// force close if we're filling the path, since fill path expects closed perimeter.
		bool forceClose = paintInfo.style != SkPaint::kStroke_Style;
		PathApproximationInfo approximationInfo(threshInvScaleX, threshInvScaleY,
		OUTLINE_REFINE_THRESHOLD);
		bool wasClosed = approximatePathOutlineVertices(path, forceClose,
		threshInvScaleX * threshInvScaleX, threshInvScaleY * threshInvScaleY,
		OUTLINE_REFINE_THRESHOLD_SQUARED, tempVertices);
		approximationInfo, tempVertices);

		if (!tempVertices.size()) {
		// path was empty, return without allocating vertex buffer
		@@ -819,10 +820,9 @@ void PathTessellator::tessellatePoints(const float* points, int count, const SkP

		// calculate outline
		Vector<Vertex> outlineVertices;
		approximatePathOutlineVertices(path, true,
		paintInfo.inverseScaleX * paintInfo.inverseScaleX,
		paintInfo.inverseScaleY * paintInfo.inverseScaleY,
		OUTLINE_REFINE_THRESHOLD_SQUARED, outlineVertices);
		PathApproximationInfo approximationInfo(paintInfo.inverseScaleX, paintInfo.inverseScaleY,
		OUTLINE_REFINE_THRESHOLD);
		approximatePathOutlineVertices(path, true, approximationInfo, outlineVertices);

		if (!outlineVertices.size()) return;

		@@ -899,9 +899,10 @@ void PathTessellator::tessellateLines(const float* points, int count, const SkPa
		// Simple path line approximation
		///////////////////////////////////////////////////////////////////////////////

		bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, float thresholdSquared,
		bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, float threshold,
		Vector<Vertex>& outputVertices) {
		return approximatePathOutlineVertices(path, true, 1.0f, 1.0f, thresholdSquared, outputVertices);
		PathApproximationInfo approximationInfo(1.0f, 1.0f, threshold);
		return approximatePathOutlineVertices(path, true, approximationInfo, outputVertices);
		}

		void pushToVector(Vector<Vertex>& vertices, float x, float y) {
		@@ -946,8 +947,7 @@ private:
		};

		bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, bool forceClose,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		Vector<Vertex>& outputVertices) {
		const PathApproximationInfo& approximationInfo, Vector<Vertex>& outputVertices) {
		ATRACE_CALL();

		// TODO: to support joins other than sharp miter, join vertices should be labelled in the
		@@ -978,7 +978,7 @@ bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, bool fo
		pts[0].x(), pts[0].y(),
		pts[2].x(), pts[2].y(),
		pts[1].x(), pts[1].y(),
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices);
		approximationInfo, outputVertices);
		clockwiseEnforcer.addPoint(pts[1]);
		clockwiseEnforcer.addPoint(pts[2]);
		break;
		@@ -989,7 +989,7 @@ bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, bool fo
		pts[1].x(), pts[1].y(),
		pts[3].x(), pts[3].y(),
		pts[2].x(), pts[2].y(),
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices);
		approximationInfo, outputVertices);
		clockwiseEnforcer.addPoint(pts[1]);
		clockwiseEnforcer.addPoint(pts[2]);
		clockwiseEnforcer.addPoint(pts[3]);
		@@ -998,14 +998,14 @@ bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, bool fo
		ALOGV("kConic_Verb");
		SkAutoConicToQuads converter;
		const SkPoint* quads = converter.computeQuads(pts, iter.conicWeight(),
		thresholdSquared);
		approximationInfo.thresholdForConicQuads);
		for (int i = 0; i < converter.countQuads(); ++i) {
		const int offset = 2 * i;
		recursiveQuadraticBezierVertices(
		quads[offset].x(), quads[offset].y(),
		quads[offset+2].x(), quads[offset+2].y(),
		quads[offset+1].x(), quads[offset+1].y(),
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices);
		approximationInfo, outputVertices);
		}
		clockwiseEnforcer.addPoint(pts[1]);
		clockwiseEnforcer.addPoint(pts[2]);
		@@ -1031,12 +1031,23 @@ bool PathTessellator::approximatePathOutlineVertices(const SkPath& path, bool fo

		///////////////////////////////////////////////////////////////////////////////
		// Bezier approximation
		//
		// All the inputs and outputs here are in path coordinates.
		// We convert the error threshold from screen coordinates into path coordinates.
		///////////////////////////////////////////////////////////////////////////////

		// Get a threshold in path coordinates, by scaling the thresholdSquared from screen coordinates.
		// TODO: Document the math behind this algorithm.
		static inline float getThreshold(const PathApproximationInfo& info, float dx, float dy) {
		// multiplying by sqrInvScaleY/X equivalent to multiplying in dimensional scale factors
		float scale = (dx * dx * info.sqrInvScaleY + dy * dy * info.sqrInvScaleX);
		return info.thresholdSquared * scale;
		}

		void PathTessellator::recursiveCubicBezierVertices(
		float p1x, float p1y, float c1x, float c1y,
		float p2x, float p2y, float c2x, float c2y,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		const PathApproximationInfo& approximationInfo,
		Vector<Vertex>& outputVertices, int depth) {
		float dx = p2x - p1x;
		float dy = p2y - p1y;
		@@ -1044,9 +1055,8 @@ void PathTessellator::recursiveCubicBezierVertices(
		float d2 = fabs((c2x - p2x) * dy - (c2y - p2y) * dx);
		float d = d1 + d2;

		// multiplying by sqrInvScaleY/X equivalent to multiplying in dimensional scale factors
		if (depth >= MAX_DEPTH
		\|\| d * d <= thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
		\|\| d * d <= getThreshold(approximationInfo, dx, dy)) {
		// below thresh, draw line by adding endpoint
		pushToVector(outputVertices, p2x, p2y);
		} else {
		@@ -1070,11 +1080,11 @@ void PathTessellator::recursiveCubicBezierVertices(
		recursiveCubicBezierVertices(
		p1x, p1y, p1c1x, p1c1y,
		mx, my, p1c1c2x, p1c1c2y,
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices, depth + 1);
		approximationInfo, outputVertices, depth + 1);
		recursiveCubicBezierVertices(
		mx, my, p2c1c2x, p2c1c2y,
		p2x, p2y, p2c2x, p2c2y,
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices, depth + 1);
		approximationInfo, outputVertices, depth + 1);
		}
		}

		@@ -1082,15 +1092,15 @@ void PathTessellator::recursiveQuadraticBezierVertices(
		float ax, float ay,
		float bx, float by,
		float cx, float cy,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		const PathApproximationInfo& approximationInfo,
		Vector<Vertex>& outputVertices, int depth) {
		float dx = bx - ax;
		float dy = by - ay;
		// d is the cross product of vector (B-A) and (C-B).
		float d = (cx - bx) * dy - (cy - by) * dx;

		// multiplying by sqrInvScaleY/X equivalent to multiplying in dimensional scale factors
		if (depth >= MAX_DEPTH
		\|\| d * d <= thresholdSquared * (dx * dx * sqrInvScaleY + dy * dy * sqrInvScaleX)) {
		\|\| d * d <= getThreshold(approximationInfo, dx, dy)) {
		// below thresh, draw line by adding endpoint
		pushToVector(outputVertices, bx, by);
		} else {
		@@ -1104,9 +1114,9 @@ void PathTessellator::recursiveQuadraticBezierVertices(
		float my = (acy + bcy) * 0.5f;

		recursiveQuadraticBezierVertices(ax, ay, mx, my, acx, acy,
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices, depth + 1);
		approximationInfo, outputVertices, depth + 1);
		recursiveQuadraticBezierVertices(mx, my, bx, by, bcx, bcy,
		sqrInvScaleX, sqrInvScaleY, thresholdSquared, outputVertices, depth + 1);
		approximationInfo, outputVertices, depth + 1);
		}
		}

libs/hwui/PathTessellator.h

+25 −6

Original line number	Diff line number	Diff line
		@@ -27,6 +27,26 @@
		namespace android {
		namespace uirenderer {

		/**
		* Structure used for threshold values in outline path tessellation.
		*
		* TODO: PaintInfo should store one of this object, and initialized all values in constructor
		* depending on its type (point, line or path).
		*/
		struct PathApproximationInfo {
		PathApproximationInfo(float invScaleX, float invScaleY, float pixelThreshold)
		: thresholdSquared(pixelThreshold * pixelThreshold)
		, sqrInvScaleX(invScaleX * invScaleX)
		, sqrInvScaleY(invScaleY * invScaleY)
		, thresholdForConicQuads(pixelThreshold * MathUtils::min(invScaleX, invScaleY) / 2.0f) {
		};

		const float thresholdSquared;
		const float sqrInvScaleX;
		const float sqrInvScaleY;
		const float thresholdForConicQuads;
		};

		class PathTessellator {
		public:
		/**
		@@ -85,16 +105,15 @@ public:
		* Approximates a convex outline into a clockwise Vector of 2d vertices.
		*
		* @param path The outline to be approximated
		* @param thresholdSquared The threshold of acceptable error (in pixels) when approximating
		* @param threshold The threshold of acceptable error (in pixels) when approximating
		* @param outputVertices An empty Vector which will be populated with the output
		*/
		static bool approximatePathOutlineVertices(const SkPath &path, float thresholdSquared,
		static bool approximatePathOutlineVertices(const SkPath &path, float threshold,
		Vector<Vertex> &outputVertices);

		private:
		static bool approximatePathOutlineVertices(const SkPath &path, bool forceClose,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		Vector<Vertex> &outputVertices);
		const PathApproximationInfo& approximationInfo, Vector<Vertex> &outputVertices);

		/*
		endpoints a & b,
		@@ -104,7 +123,7 @@ private:
		float ax, float ay,
		float bx, float by,
		float cx, float cy,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		const PathApproximationInfo& approximationInfo,
		Vector<Vertex> &outputVertices, int depth = 0);

		/*
		@@ -116,7 +135,7 @@ private:
		float c1x, float c1y,
		float p2x, float p2y,
		float c2x, float c2y,
		float sqrInvScaleX, float sqrInvScaleY, float thresholdSquared,
		const PathApproximationInfo& approximationInfo,
		Vector<Vertex> &outputVertices, int depth = 0);
		};

libs/hwui/TessellationCache.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -226,9 +226,9 @@ static void tessellateShadows(

		// tessellate caster outline into a 2d polygon
		Vector<Vertex> casterVertices2d;
		const float casterRefinementThresholdSquared = 4.0f;
		const float casterRefinementThreshold = 2.0f;
		PathTessellator::approximatePathOutlineVertices(*casterPerimeter,
		casterRefinementThresholdSquared, casterVertices2d);
		casterRefinementThreshold, casterVertices2d);

		// Shadow requires CCW for now. TODO: remove potential double-reverse
		reverseVertexArray(casterVertices2d.editArray(), casterVertices2d.size());