Merge "Simplify umbra calculation" (494db9e4) · Commits · e / os / android_frameworks_base

libs/hwui/SpotShadow.cpp

+8 −18

Original line number	Diff line number	Diff line
		@@ -743,9 +743,10 @@ void SpotShadow::generateTriangleStrip(const Vector2* penumbra, int penumbraLeng
		int stripSize = getStripSize(rays, layers);
		AlphaVertex* shadowVertices = shadowTriangleStrip.alloc<AlphaVertex>(stripSize);
		int currentIndex = 0;
		int firstInLayer = 0;
		// Calculate the vertex values in the penumbra area.
		for (int r = 0; r < layers; r++) {
		int firstInEachLayer = currentIndex;
		firstInLayer = currentIndex;
		for (int i = 0; i < rays; i++) {
		float dx = sinf(step * i);
		float dy = cosf(step * i);
		@@ -755,19 +756,17 @@ void SpotShadow::generateTriangleStrip(const Vector2* penumbra, int penumbraLeng
		float deltaDist = layerRatio * (umbraDistPerRay[i] - penumbraDistPerRay[i]);
		float currentDist = penumbraDistPerRay[i] + deltaDist;
		float op = calculateOpacity(layerRatio, deltaDist);
		AlphaVertex::set(&shadowVertices[currentIndex],
		AlphaVertex::set(&shadowVertices[currentIndex++],
		dx * currentDist + centroid.x,
		dy * currentDist + centroid.y,
		layerRatio * op * strength);
		currentIndex++;
		}
		}

		// Duplicate the vertices from one layer to another one to make triangle
		// strip.
		shadowVertices[currentIndex++] = shadowVertices[firstInEachLayer];
		firstInEachLayer++;
		shadowVertices[currentIndex++] = shadowVertices[firstInEachLayer];
		shadowVertices[currentIndex++] = shadowVertices[firstInLayer + 0];
		shadowVertices[currentIndex++] = shadowVertices[firstInLayer + 1];
		}

		int lastInPenumbra = currentIndex - 1;
		@@ -779,23 +778,14 @@ void SpotShadow::generateTriangleStrip(const Vector2* penumbra, int penumbraLeng
		int firstInUmbra = currentIndex;

		// traverse the umbra area in a zig zag pattern for strips.
		const int innerRingStartIndex = firstInLayer + 1;
		for (int k = 0; k < rays; k++) {
		int i = k / 2;
		if ((k & 1) == 1) {
		i = rays - i - 1;
		}
		float dx = sinf(step * i);
		float dy = cosf(step * i);

		float ratio = 1.0;
		float deltaDist = ratio * (umbraDistPerRay[i] - penumbraDistPerRay[i]);
		float currentDist = penumbraDistPerRay[i] + deltaDist;
		float op = calculateOpacity(ratio, deltaDist);
		AlphaVertex::set(&shadowVertices[currentIndex],
		dx * currentDist + centroid.x, dy * currentDist + centroid.y,
		ratio * op * strength);
		currentIndex++;

		// copy already computed values for umbra vertices
		shadowVertices[currentIndex++] = shadowVertices[innerRingStartIndex + i * 2];
		}

		// Back fill the one vertex for jumping from penumbra to umbra.