[RenderEngine] Refactor the generation of EOTF, OOTF and OETF.
Previously the generation of EOTF, OOTF and OETF are in fragment shader
generation function, this patch refactors them out as their own functions.
BUG: 73825729
Test: build, flash
Change-Id: I4701c04252fb35dfe1676570b775a94108610b9f
diff --git a/services/surfaceflinger/RenderEngine/ProgramCache.cpp b/services/surfaceflinger/RenderEngine/ProgramCache.cpp
index d1887ee..fb63296 100644
--- a/services/surfaceflinger/RenderEngine/ProgramCache.cpp
+++ b/services/surfaceflinger/RenderEngine/ProgramCache.cpp
@@ -168,6 +168,227 @@
return needs;
}
+// Generate EOTF that converts signal values to relative display light,
+// both normalized to [0, 1].
+void ProgramCache::generateEOTF(Formatter& fs, const Key& needs) {
+ switch (needs.getInputTF()) {
+ case Key::INPUT_TF_SRGB:
+ fs << R"__SHADER__(
+ float EOTF_sRGB(float srgb) {
+ return srgb <= 0.04045 ? srgb / 12.92 : pow((srgb + 0.055) / 1.055, 2.4);
+ }
+
+ vec3 EOTF_sRGB(const vec3 srgb) {
+ return vec3(EOTF_sRGB(srgb.r), EOTF_sRGB(srgb.g), EOTF_sRGB(srgb.b));
+ }
+
+ vec3 EOTF(const vec3 srgb) {
+ return sign(srgb.rgb) * EOTF_sRGB(abs(srgb.rgb));
+ }
+ )__SHADER__";
+ break;
+ case Key::INPUT_TF_ST2084:
+ fs << R"__SHADER__(
+ vec3 EOTF(const highp vec3 color) {
+ const highp float m1 = (2610.0 / 4096.0) / 4.0;
+ const highp float m2 = (2523.0 / 4096.0) * 128.0;
+ const highp float c1 = (3424.0 / 4096.0);
+ const highp float c2 = (2413.0 / 4096.0) * 32.0;
+ const highp float c3 = (2392.0 / 4096.0) * 32.0;
+
+ highp vec3 tmp = pow(color, 1.0 / vec3(m2));
+ tmp = max(tmp - c1, 0.0) / (c2 - c3 * tmp);
+ return pow(tmp, 1.0 / vec3(m1));
+ }
+ )__SHADER__";
+ break;
+ case Key::INPUT_TF_HLG:
+ fs << R"__SHADER__(
+ highp float EOTF_channel(const highp float channel) {
+ const highp float a = 0.17883277;
+ const highp float b = 0.28466892;
+ const highp float c = 0.55991073;
+ return channel <= 0.5 ? channel * channel / 3.0 :
+ (exp((channel - c) / a) + b) / 12.0;
+ }
+
+ vec3 EOTF(const highp vec3 color) {
+ return vec3(EOTF_channel(color.r), EOTF_channel(color.g),
+ EOTF_channel(color.b));
+ }
+ )__SHADER__";
+ break;
+ default:
+ fs << R"__SHADER__(
+ vec3 EOTF(const vec3 linear) {
+ return linear;
+ }
+ )__SHADER__";
+ break;
+ }
+}
+
+// Generate OOTF that modifies the relative scence light to relative display light.
+void ProgramCache::generateOOTF(Formatter& fs, const Key& needs) {
+ fs << R"__SHADER__(
+ highp float CalculateY(const highp vec3 color) {
+ // BT2020 standard uses the unadjusted KR = 0.2627,
+ // KB = 0.0593 luminance interpretation for RGB conversion.
+ return color.r * 0.262700 + color.g * 0.677998 + color.b * 0.059302;
+ }
+ )__SHADER__";
+
+ // Generate OOTF that modifies the relative display light.
+ switch(needs.getInputTF()) {
+ case Key::INPUT_TF_ST2084:
+ fs << R"__SHADER__(
+ highp vec3 OOTF(const highp vec3 color) {
+ const float maxLumi = 10000.0;
+ const float maxMasteringLumi = 1000.0;
+ const float maxContentLumi = 1000.0;
+ const float maxInLumi = min(maxMasteringLumi, maxContentLumi);
+ const float maxOutLumi = 500.0;
+
+ // Calculate Y value in XYZ color space.
+ float colorY = CalculateY(color);
+
+ // convert to nits first
+ float nits = colorY * maxLumi;
+
+ // clamp to max input luminance
+ nits = clamp(nits, 0.0, maxInLumi);
+
+ // scale [0.0, maxInLumi] to [0.0, maxOutLumi]
+ if (maxInLumi <= maxOutLumi) {
+ nits *= maxOutLumi / maxInLumi;
+ } else {
+ // three control points
+ const float x0 = 10.0;
+ const float y0 = 17.0;
+ const float x1 = maxOutLumi * 0.75;
+ const float y1 = x1;
+ const float x2 = x1 + (maxInLumi - x1) / 2.0;
+ const float y2 = y1 + (maxOutLumi - y1) * 0.75;
+
+ // horizontal distances between the last three control points
+ const float h12 = x2 - x1;
+ const float h23 = maxInLumi - x2;
+ // tangents at the last three control points
+ const float m1 = (y2 - y1) / h12;
+ const float m3 = (maxOutLumi - y2) / h23;
+ const float m2 = (m1 + m3) / 2.0;
+
+ if (nits < x0) {
+ // scale [0.0, x0] to [0.0, y0] linearly
+ const float slope = y0 / x0;
+ nits *= slope;
+ } else if (nits < x1) {
+ // scale [x0, x1] to [y0, y1] linearly
+ const float slope = (y1 - y0) / (x1 - x0);
+ nits = y0 + (nits - x0) * slope;
+ } else if (nits < x2) {
+ // scale [x1, x2] to [y1, y2] using Hermite interp
+ float t = (nits - x1) / h12;
+ nits = (y1 * (1.0 + 2.0 * t) + h12 * m1 * t) * (1.0 - t) * (1.0 - t) +
+ (y2 * (3.0 - 2.0 * t) + h12 * m2 * (t - 1.0)) * t * t;
+ } else {
+ // scale [x2, maxInLumi] to [y2, maxOutLumi] using Hermite interp
+ float t = (nits - x2) / h23;
+ nits = (y2 * (1.0 + 2.0 * t) + h23 * m2 * t) * (1.0 - t) * (1.0 - t) +
+ (maxOutLumi * (3.0 - 2.0 * t) + h23 * m3 * (t - 1.0)) * t * t;
+ }
+ }
+
+ // convert back to [0.0, 1.0]
+ float targetY = nits / maxOutLumi;
+ return color * (targetY / max(1e-6, colorY));
+ }
+ )__SHADER__";
+ break;
+ case Key::INPUT_TF_HLG:
+ fs << R"__SHADER__(
+ highp vec3 OOTF(const highp vec3 color) {
+ const float maxOutLumi = 500.0;
+ const float gamma = 1.2 + 0.42 * log(maxOutLumi / 1000.0) / log(10.0);
+ // The formula is:
+ // alpha * pow(Y, gamma - 1.0) * color + beta;
+ // where alpha is 1.0, beta is 0.0 as recommended in
+ // Rec. ITU-R BT.2100-1 TABLE 5.
+ return pow(CalculateY(color), gamma - 1.0) * color;
+ }
+ )__SHADER__";
+ break;
+ default:
+ fs << R"__SHADER__(
+ highp vec3 OOTF(const highp vec3 color) {
+ return color;
+ }
+ )__SHADER__";
+ break;
+ }
+}
+
+// Generate OETF that converts relative display light to signal values,
+// both normalized to [0, 1]
+void ProgramCache::generateOETF(Formatter& fs, const Key& needs) {
+ switch (needs.getOutputTF()) {
+ case Key::OUTPUT_TF_SRGB:
+ fs << R"__SHADER__(
+ float OETF_sRGB(const float linear) {
+ return linear <= 0.0031308 ?
+ linear * 12.92 : (pow(linear, 1.0 / 2.4) * 1.055) - 0.055;
+ }
+
+ vec3 OETF_sRGB(const vec3 linear) {
+ return vec3(OETF_sRGB(linear.r), OETF_sRGB(linear.g), OETF_sRGB(linear.b));
+ }
+
+ vec3 OETF(const vec3 linear) {
+ return sign(linear.rgb) * OETF_sRGB(abs(linear.rgb));
+ }
+ )__SHADER__";
+ break;
+ case Key::OUTPUT_TF_ST2084:
+ fs << R"__SHADER__(
+ vec3 OETF(const vec3 linear) {
+ const float m1 = (2610.0 / 4096.0) / 4.0;
+ const float m2 = (2523.0 / 4096.0) * 128.0;
+ const float c1 = (3424.0 / 4096.0);
+ const float c2 = (2413.0 / 4096.0) * 32.0;
+ const float c3 = (2392.0 / 4096.0) * 32.0;
+
+ vec3 tmp = pow(linear, vec3(m1));
+ tmp = (c1 + c2 * tmp) / (1.0 + c3 * tmp);
+ return pow(tmp, vec3(m2));
+ }
+ )__SHADER__";
+ break;
+ case Key::OUTPUT_TF_HLG:
+ fs << R"__SHADER__(
+ highp float OETF_channel(const highp float channel) {
+ const highp float a = 0.17883277;
+ const highp float b = 0.28466892;
+ const highp float c = 0.55991073;
+ return channel <= 1.0 / 12.0 ? sqrt(3.0 * channel) :
+ a * log(12.0 * channel - b) + c;
+ }
+
+ vec3 OETF(const highp vec3 color) {
+ return vec3(OETF_channel(color.r), OETF_channel(color.g),
+ OETF_channel(color.b));
+ }
+ )__SHADER__";
+ break;
+ default:
+ fs << R"__SHADER__(
+ vec3 OETF(const vec3 linear) {
+ return linear;
+ }
+ )__SHADER__";
+ break;
+ }
+}
+
String8 ProgramCache::generateVertexShader(const Key& needs) {
Formatter vs;
if (needs.isTexturing()) {
@@ -223,221 +444,9 @@
if (needs.hasColorMatrix()) {
fs << "uniform mat4 colorMatrix;";
- // Generate EOTF that converts signal values to relative display light,
- // both normalized to [0, 1].
- switch (needs.getInputTF()) {
- case Key::INPUT_TF_LINEAR:
- default:
- fs << R"__SHADER__(
- vec3 EOTF(const vec3 linear) {
- return linear;
- }
- )__SHADER__";
- break;
- case Key::INPUT_TF_SRGB:
- fs << R"__SHADER__(
- float EOTF_sRGB(float srgb) {
- return srgb <= 0.04045 ? srgb / 12.92 : pow((srgb + 0.055) / 1.055, 2.4);
- }
-
- vec3 EOTF_sRGB(const vec3 srgb) {
- return vec3(EOTF_sRGB(srgb.r), EOTF_sRGB(srgb.g), EOTF_sRGB(srgb.b));
- }
-
- vec3 EOTF(const vec3 srgb) {
- return sign(srgb.rgb) * EOTF_sRGB(abs(srgb.rgb));
- }
- )__SHADER__";
- break;
- case Key::INPUT_TF_ST2084:
- fs << R"__SHADER__(
- vec3 EOTF(const highp vec3 color) {
- const highp float m1 = (2610.0 / 4096.0) / 4.0;
- const highp float m2 = (2523.0 / 4096.0) * 128.0;
- const highp float c1 = (3424.0 / 4096.0);
- const highp float c2 = (2413.0 / 4096.0) * 32.0;
- const highp float c3 = (2392.0 / 4096.0) * 32.0;
-
- highp vec3 tmp = pow(color, 1.0 / vec3(m2));
- tmp = max(tmp - c1, 0.0) / (c2 - c3 * tmp);
- return pow(tmp, 1.0 / vec3(m1));
- }
- )__SHADER__";
- break;
- case Key::INPUT_TF_HLG:
- fs << R"__SHADER__(
- highp float EOTF_channel(const highp float channel) {
- const highp float a = 0.17883277;
- const highp float b = 0.28466892;
- const highp float c = 0.55991073;
- return channel <= 0.5 ? channel * channel / 3.0 :
- (exp((channel - c) / a) + b) / 12.0;
- }
-
- vec3 EOTF(const highp vec3 color) {
- return vec3(EOTF_channel(color.r), EOTF_channel(color.g),
- EOTF_channel(color.b));
- }
- )__SHADER__";
- break;
- }
-
- fs << R"__SHADER__(
- highp float CalculateY(const highp vec3 color) {
- // BT2020 standard uses the unadjusted KR = 0.2627,
- // KB = 0.0593 luminance interpretation for RGB conversion.
- return color.r * 0.262700 + color.g * 0.677998 +
- color.b * 0.059302;
- }
- )__SHADER__";
-
- // Generate OOTF that modifies the relative display light.
- switch(needs.getInputTF()) {
- case Key::INPUT_TF_ST2084:
- fs << R"__SHADER__(
- highp vec3 OOTF(const highp vec3 color) {
- const float maxLumi = 10000.0;
- const float maxMasteringLumi = 1000.0;
- const float maxContentLumi = 1000.0;
- const float maxInLumi = min(maxMasteringLumi, maxContentLumi);
- const float maxOutLumi = 500.0;
-
- // Calculate Y value in XYZ color space.
- float colorY = CalculateY(color);
-
- // convert to nits first
- float nits = colorY * maxLumi;
-
- // clamp to max input luminance
- nits = clamp(nits, 0.0, maxInLumi);
-
- // scale [0.0, maxInLumi] to [0.0, maxOutLumi]
- if (maxInLumi <= maxOutLumi) {
- nits *= maxOutLumi / maxInLumi;
- } else {
- // three control points
- const float x0 = 10.0;
- const float y0 = 17.0;
- const float x1 = maxOutLumi * 0.75;
- const float y1 = x1;
- const float x2 = x1 + (maxInLumi - x1) / 2.0;
- const float y2 = y1 + (maxOutLumi - y1) * 0.75;
-
- // horizontal distances between the last three control points
- const float h12 = x2 - x1;
- const float h23 = maxInLumi - x2;
- // tangents at the last three control points
- const float m1 = (y2 - y1) / h12;
- const float m3 = (maxOutLumi - y2) / h23;
- const float m2 = (m1 + m3) / 2.0;
-
- if (nits < x0) {
- // scale [0.0, x0] to [0.0, y0] linearly
- const float slope = y0 / x0;
- nits *= slope;
- } else if (nits < x1) {
- // scale [x0, x1] to [y0, y1] linearly
- const float slope = (y1 - y0) / (x1 - x0);
- nits = y0 + (nits - x0) * slope;
- } else if (nits < x2) {
- // scale [x1, x2] to [y1, y2] using Hermite interp
- float t = (nits - x1) / h12;
- nits = (y1 * (1.0 + 2.0 * t) + h12 * m1 * t) * (1.0 - t) * (1.0 - t) +
- (y2 * (3.0 - 2.0 * t) + h12 * m2 * (t - 1.0)) * t * t;
- } else {
- // scale [x2, maxInLumi] to [y2, maxOutLumi] using Hermite interp
- float t = (nits - x2) / h23;
- nits = (y2 * (1.0 + 2.0 * t) + h23 * m2 * t) * (1.0 - t) * (1.0 - t) +
- (maxOutLumi * (3.0 - 2.0 * t) + h23 * m3 * (t - 1.0)) * t * t;
- }
- }
-
- // convert back to [0.0, 1.0]
- float targetY = nits / maxOutLumi;
- return color * (targetY / max(1e-6, colorY));
- }
- )__SHADER__";
- break;
- case Key::INPUT_TF_HLG:
- fs << R"__SHADER__(
- highp vec3 OOTF(const highp vec3 color) {
- const float maxOutLumi = 500.0;
- const float gamma = 1.2 + 0.42 * log(maxOutLumi / 1000.0) / log(10.0);
- // The formula is:
- // alpha * pow(Y, gamma - 1.0) * color + beta;
- // where alpha is 1.0, beta is 0.0 as recommended in
- // Rec. ITU-R BT.2100-1 TABLE 5.
- return pow(CalculateY(color), gamma - 1.0) * color;
- }
- )__SHADER__";
- break;
- default:
- fs << R"__SHADER__(
- highp vec3 OOTF(const highp vec3 color) {
- return color;
- }
- )__SHADER__";
- }
-
- // Generate OETF that converts relative display light to signal values,
- // both normalized to [0, 1]
- switch (needs.getOutputTF()) {
- case Key::OUTPUT_TF_LINEAR:
- default:
- fs << R"__SHADER__(
- vec3 OETF(const vec3 linear) {
- return linear;
- }
- )__SHADER__";
- break;
- case Key::OUTPUT_TF_SRGB:
- fs << R"__SHADER__(
- float OETF_sRGB(const float linear) {
- return linear <= 0.0031308 ?
- linear * 12.92 : (pow(linear, 1.0 / 2.4) * 1.055) - 0.055;
- }
-
- vec3 OETF_sRGB(const vec3 linear) {
- return vec3(OETF_sRGB(linear.r), OETF_sRGB(linear.g), OETF_sRGB(linear.b));
- }
-
- vec3 OETF(const vec3 linear) {
- return sign(linear.rgb) * OETF_sRGB(abs(linear.rgb));
- }
- )__SHADER__";
- break;
- case Key::OUTPUT_TF_ST2084:
- fs << R"__SHADER__(
- vec3 OETF(const vec3 linear) {
- const float m1 = (2610.0 / 4096.0) / 4.0;
- const float m2 = (2523.0 / 4096.0) * 128.0;
- const float c1 = (3424.0 / 4096.0);
- const float c2 = (2413.0 / 4096.0) * 32.0;
- const float c3 = (2392.0 / 4096.0) * 32.0;
-
- vec3 tmp = pow(linear, vec3(m1));
- tmp = (c1 + c2 * tmp) / (1.0 + c3 * tmp);
- return pow(tmp, vec3(m2));
- }
- )__SHADER__";
- break;
- case Key::OUTPUT_TF_HLG:
- fs << R"__SHADER__(
- highp float OETF_channel(const highp float channel) {
- const highp float a = 0.17883277;
- const highp float b = 0.28466892;
- const highp float c = 0.55991073;
- return channel <= 1.0 / 12.0 ? sqrt(3.0 * channel) :
- a * log(12.0 * channel - b) + c;
- }
-
- vec3 OETF(const highp vec3 color) {
- return vec3(OETF_channel(color.r), OETF_channel(color.g),
- OETF_channel(color.b));
- }
- )__SHADER__";
- break;
- }
+ generateEOTF(fs, needs);
+ generateOOTF(fs, needs);
+ generateOETF(fs, needs);
}
fs << "void main(void) {" << indent;