Merge "Gradients are now an absurd Chimera" (3f57d7f7) · Commits · e / os / android_frameworks_base

libs/hwui/GradientCache.cpp

+4 −0

Original line number	Diff line number	Diff line
		@@ -205,6 +205,10 @@ void GradientCache::mixFloats(const FloatColor& start, const FloatColor& end,
		d++ = a (start.g * oppAmount + end.g * amount);
		d++ = a (start.b * oppAmount + end.b * amount);
		#else
		// What we're doing to the alpha channel here is technically incorrect
		// but reproduces Android's old behavior when the alpha was pre-multiplied
		// with gamma-encoded colors
		a = EOCF_sRGB(a);
		d++ = a OECF_sRGB(start.r * oppAmount + end.r * amount);
		d++ = a OECF_sRGB(start.g * oppAmount + end.g * amount);
		d++ = a OECF_sRGB(start.b * oppAmount + end.b * amount);

libs/hwui/ProgramCache.cpp

+34 −17

Original line number	Diff line number	Diff line
		@@ -164,24 +164,39 @@ const char* gFS_Uniforms_HasRoundRectClip =
		// Dithering must be done in the quantization space
		// When we are writing to an sRGB framebuffer, we must do the following:
		// EOCF(OECF(color) + dither)
		// We approximate the transfer functions with gamma 2.0 to avoid branches and pow()
		// The dithering pattern is generated with a triangle noise generator in the range [-0.0,1.0]
		// TODO: Handle linear fp16 render targets
		const char* gFS_Gradient_Functions =
		"\nfloat triangleNoise(const highp vec2 n) {\n"
		" highp vec2 p = fract(n * vec2(5.3987, 5.4421));\n"
		" p += dot(p.yx, p.xy + vec2(21.5351, 14.3137));\n"
		" highp float xy = p.x * p.y;\n"
		" return fract(xy * 95.4307) + fract(xy * 75.04961) - 1.0;\n"
		"}\n";
		const char* gFS_Gradient_Functions = R"__SHADER__(
		float triangleNoise(const highp vec2 n) {
		highp vec2 p = fract(n * vec2(5.3987, 5.4421));
		p += dot(p.yx, p.xy + vec2(21.5351, 14.3137));
		highp float xy = p.x * p.y;
		return fract(xy * 95.4307) + fract(xy * 75.04961) - 1.0;
		}

		float OECF_sRGB(const float linear) {
		// IEC 61966-2-1:1999
		return linear <= 0.0031308 ? linear * 12.92 : (pow(linear, 1.0 / 2.4) * 1.055) - 0.055;
		}

		vec3 OECF_sRGB(const vec3 linear) {
		return vec3(OECF_sRGB(linear.r), OECF_sRGB(linear.g), OECF_sRGB(linear.b));
		}

		float EOCF_sRGB(float srgb) {
		// IEC 61966-2-1:1999
		return srgb <= 0.04045 ? srgb / 12.92 : pow((srgb + 0.055) / 1.055, 2.4);
		}
		)__SHADER__";
		const char* gFS_Gradient_Preamble[2] = {
		// Linear framebuffer
		"\nvec4 dither(const vec4 color) {\n"
		" return vec4(color.rgb + (triangleNoise(gl_FragCoord.xy * screenSize.xy) / 255.0), color.a);\n"
		"}\n"
		"\nvec4 gammaMix(const vec4 a, const vec4 b, float v) {\n"
		" vec4 c = pow(mix(a, b, v), vec4(vec3(1.0 / 2.2), 1.0));\n"
		" return vec4(c.rgb * c.a, c.a);\n"
		" vec4 c = mix(a, b, v);\n"
		" c.a = EOCF_sRGB(c.a);\n" // This is technically incorrect but preserves compatibility
		" return vec4(OECF_sRGB(c.rgb) * c.a, c.a);\n"
		"}\n",
		// sRGB framebuffer
		"\nvec4 dither(const vec4 color) {\n"
		@@ -200,13 +215,15 @@ const char* gFS_Gradient_Preamble[2] = {
		// The gamma coefficient is chosen to thicken or thin the text accordingly
		// The dot product used to compute the luminance could be approximated with
		// a simple max(color.r, color.g, color.b)
		const char* gFS_Gamma_Preamble =
		"\n#define GAMMA (%.2f)\n"
		"#define GAMMA_INV (%.2f)\n"
		"\nfloat gamma(float a, const vec3 color) {\n"
		" float luminance = dot(color, vec3(0.2126, 0.7152, 0.0722));\n"
		" return pow(a, luminance < 0.5 ? GAMMA_INV : GAMMA);\n"
		"}\n";
		const char* gFS_Gamma_Preamble = R"__SHADER__(
		#define GAMMA (%.2f)
		#define GAMMA_INV (%.2f)

		float gamma(float a, const vec3 color) {
		float luminance = dot(color, vec3(0.2126, 0.7152, 0.0722));
		return pow(a, luminance < 0.5 ? GAMMA_INV : GAMMA);
		}
		)__SHADER__";

		const char* gFS_Main =
		"\nvoid main(void) {\n"

libs/hwui/Texture.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -44,7 +44,7 @@ static int bytesPerPixel(GLint glFormat) {
		case GL_RGBA16F:
		return 8;
		default:
		LOG_ALWAYS_FATAL("UNKNOWN FORMAT %d", glFormat);
		LOG_ALWAYS_FATAL("UNKNOWN FORMAT 0x%x", glFormat);
		}
		}