Merge "Update the shadow fall off function from cosine to gaussian." (3f6d5aa5) · Commits · e / os / android_frameworks_base

core/res/res/values/dimens.xml

+4 −4

Original line number	Diff line number	Diff line
		@@ -380,10 +380,10 @@

		<!-- Lighting and shadow properties -->
		<dimen name="light_y">-200dp</dimen>
		<dimen name="light_z">800dp</dimen>
		<dimen name="light_radius">600dp</dimen>
		<item type="dimen" format="float" name="ambient_shadow_alpha">0.075</item>
		<item type="dimen" format="float" name="spot_shadow_alpha">0.15</item>
		<dimen name="light_z">600dp</dimen>
		<dimen name="light_radius">800dp</dimen>
		<item type="dimen" format="float" name="ambient_shadow_alpha">0.039</item>
		<item type="dimen" format="float" name="spot_shadow_alpha">0.19</item>

		<!-- Floating toolbar dimensions -->
		<dimen name="floating_toolbar_height">48dp</dimen>

libs/hwui/AmbientShadow.cpp

+9 −6

Original line number	Diff line number	Diff line
		@@ -45,8 +45,9 @@
		/**
		* Other constants:
		*/
		// For the edge of the penumbra, the opacity is 0.
		#define OUTER_OPACITY (0.0f)
		// For the edge of the penumbra, the opacity is 0. After transform (1 - alpha),
		// it is 1.
		#define TRANSFORMED_OUTER_OPACITY (1.0f)

		// Once the alpha difference is greater than this threshold, we will allocate extra
		// edge vertices.
		@@ -83,11 +84,13 @@ inline float getAlphaFromFactoredZ(float factoredZ) {
		return 1.0 / (1 + MathUtils::max(factoredZ, 0.0f));
		}

		// The shader is using gaussian function e^-(1-x)(1-x)4, therefore, we transform
		// the alpha value to (1 - alpha)
		inline float getTransformedAlphaFromAlpha(float alpha) {
		return acosf(1.0f - 2.0f * alpha);
		return 1.0f - alpha;
		}

		// The output is ranged from 0 to M_PI.
		// The output is ranged from 0 to 1.
		inline float getTransformedAlphaFromFactoredZ(float factoredZ) {
		return getTransformedAlphaFromAlpha(getAlphaFromFactoredZ(factoredZ));
		}
		@@ -249,7 +252,7 @@ void AmbientShadow::createAmbientShadow(bool isCasterOpaque,
		indexBuffer[indexBufferIndex++] = vertexBufferIndex;
		indexBuffer[indexBufferIndex++] = currentInnerVertexIndex;
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++], outerVertex.x,
		outerVertex.y, OUTER_OPACITY);
		outerVertex.y, TRANSFORMED_OUTER_OPACITY);

		if (j == 0) {
		outerStart = outerVertex;
		@@ -285,7 +288,7 @@ void AmbientShadow::createAmbientShadow(bool isCasterOpaque,
		(outerLast * startWeight + outerNext * k) / extraVerticesNumber;
		indexBuffer[indexBufferIndex++] = vertexBufferIndex;
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++], currentOuter.x,
		currentOuter.y, OUTER_OPACITY);
		currentOuter.y, TRANSFORMED_OUTER_OPACITY);

		if (!isCasterOpaque) {
		umbraVertices[umbraIndex++] = vertexBufferIndex;

libs/hwui/ProgramCache.cpp

+3 −2

Original line number	Diff line number	Diff line
		@@ -240,8 +240,9 @@ const char* gFS_Main_ModulateColor =
		const char* gFS_Main_ApplyVertexAlphaLinearInterp =
		" fragColor *= alpha;\n";
		const char* gFS_Main_ApplyVertexAlphaShadowInterp =
		" fragColor *= (1.0 - cos(alpha)) / 2.0;\n";

		// Use a gaussian function for the shadow fall off. Note that alpha here
		// is actually (1.0 - alpha) for saving computation.
		" fragColor = exp(- alpha alpha * 4.0) - 0.018;\n";
		const char* gFS_Main_FetchTexture[2] = {
		// Don't modulate
		" fragColor = texture2D(baseSampler, outTexCoords);\n",

libs/hwui/SpotShadow.cpp

+7 −4

Original line number	Diff line number	Diff line
		@@ -44,6 +44,9 @@
		// For each RADIANS_DIVISOR, we would allocate one more vertex b/t the normals.
		#define SPOT_CORNER_RADIANS_DIVISOR (M_PI / SPOT_EXTRA_CORNER_VERTEX_PER_PI)

		// For performance, we use (1 - alpha) value for the shader input.
		#define TRANSFORMED_PENUMBRA_ALPHA 1.0f
		#define TRANSFORMED_UMBRA_ALPHA 0.0f

		#include <math.h>
		#include <stdlib.h>
		@@ -964,11 +967,11 @@ void SpotShadow::generateTriangleStrip(bool isCasterOpaque, float shadowStrength
		// Fill the IB and VB for the penumbra area.
		for (int i = 0; i < newPenumbraLength; i++) {
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++], newPenumbra[i].x,
		newPenumbra[i].y, 0.0f);
		newPenumbra[i].y, TRANSFORMED_PENUMBRA_ALPHA);
		}
		for (int i = 0; i < umbraLength; i++) {
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++], umbra[i].x, umbra[i].y,
		M_PI);
		TRANSFORMED_UMBRA_ALPHA);
		}

		for (int i = 0; i < verticesPairIndex; i++) {
		@@ -1008,14 +1011,14 @@ void SpotShadow::generateTriangleStrip(bool isCasterOpaque, float shadowStrength
		indexBuffer[indexBufferIndex++] = newPenumbraLength + i;
		indexBuffer[indexBufferIndex++] = vertexBufferIndex;
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++],
		closerVertex.x, closerVertex.y, M_PI);
		closerVertex.x, closerVertex.y, TRANSFORMED_UMBRA_ALPHA);
		}
		} else {
		// If there is no occluded umbra at all, then draw the triangle fan
		// starting from the centroid to all umbra vertices.
		int lastCentroidIndex = vertexBufferIndex;
		AlphaVertex::set(&shadowVertices[vertexBufferIndex++], centroid.x,
		centroid.y, M_PI);
		centroid.y, TRANSFORMED_UMBRA_ALPHA);
		for (int i = 0; i < umbraLength; i++) {
		indexBuffer[indexBufferIndex++] = newPenumbraLength + i;
		indexBuffer[indexBufferIndex++] = lastCentroidIndex;