added p3->srgb_xr transform

Author: gaaclarke

display_list/dl_color.cc

@@ -6,6 +6,35 @@
 
 namespace flutter {
 
+namespace {
+const std::array<DlScalar, 12> kP3ToSrgb = {
+    1.306671048092539,  -0.298061942172353,
+    0.213228303487995,  -0.213580156254466,  //
+    -0.117390025596251, 1.127722006101976,
+    0.109727644608938,  -0.109450321455370,  //
+    0.214813187718391,  0.054268702864647,
+    1.406898424029350,  -0.364892765879631};
+
+DlColor transform(const DlColor& color,
+                  const std::array<DlScalar, 12>& matrix,
+                  DlColorSpace color_space) {
+  return DlColor(color.getAlphaF(),
+                 matrix[0] * color.getRedF() +        //
+                     matrix[1] * color.getGreenF() +  //
+                     matrix[2] * color.getBlueF() +   //
+                     matrix[3],                       //
+                 matrix[4] * color.getRedF() +        //
+                     matrix[5] * color.getGreenF() +  //
+                     matrix[6] * color.getBlueF() +   //
+                     matrix[7],                       //
+                 matrix[8] * color.getRedF() +        //
+                     matrix[9] * color.getGreenF() +  //
+                     matrix[10] * color.getBlueF() +  //
+                     matrix[11],                      //
+                 color_space);
+}
+}  // namespace
+
 DlColor DlColor::withColorSpace(DlColorSpace color_space) const {
   switch (color_space_) {
     case DlColorSpace::kSRGB:
@@ -36,8 +65,7 @@ DlColor DlColor::withColorSpace(DlColorSpace color_space) const {
           FML_CHECK(false) << "not implemented";
           return *this;
         case DlColorSpace::kExtendedSRGB:
-          FML_CHECK(false) << "not implemented";
-          return *this;
+          return transform(*this, kP3ToSrgb, DlColorSpace::kExtendedSRGB);
         case DlColorSpace::kDisplayP3:
           return *this;
       }

display_list/dl_color_unittests.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "flutter/display_list/dl_color.h"
+#include "flutter/testing/display_list_testing.h"
 #include "flutter/testing/testing.h"
 
 #include "third_party/skia/include/core/SkColor.h"
@@ -269,6 +270,25 @@ TEST(DisplayListColor, ColorSpaceP3ToP3) {
             p3.withColorSpace(DlColorSpace::kDisplayP3));
 }
 
+TEST(DisplayListColor, ColorSpaceP3ToExtendedSRGB) {
+  DlColor red(0.9, 1.0, 0.0, 0.0, DlColorSpace::kDisplayP3);
+  EXPECT_TRUE(
+      DlColor(0.9, 1.0931, -0.2268, -0.1501, DlColorSpace::kExtendedSRGB)
+          .isClose(red.withColorSpace(DlColorSpace::kExtendedSRGB)))
+      << red.withColorSpace(DlColorSpace::kExtendedSRGB);
+
+  DlColor green(0.9, 0.0, 1.0, 0.0, DlColorSpace::kDisplayP3);
+  EXPECT_TRUE(
+      DlColor(0.9, -0.5116, 1.0183, -0.3106, DlColorSpace::kExtendedSRGB)
+          .isClose(green.withColorSpace(DlColorSpace::kExtendedSRGB)))
+      << green.withColorSpace(DlColorSpace::kExtendedSRGB);
+
+  DlColor blue(0.9, 0.0, 0.0, 1.0, DlColorSpace::kDisplayP3);
+  EXPECT_TRUE(DlColor(0.9, -0.0004, 0.0003, 1.0420, DlColorSpace::kExtendedSRGB)
+                  .isClose(blue.withColorSpace(DlColorSpace::kExtendedSRGB)))
+      << blue.withColorSpace(DlColorSpace::kExtendedSRGB);
+}
+
 TEST(DisplayListColor, isClose) {
   EXPECT_TRUE(DlColor(0xffaabbcc).isClose(DlColor(0xffaabbcc)));
 }

testing/display_list_testing.cc

@@ -284,7 +284,24 @@ std::ostream& operator<<(std::ostream& os, const DlFilterMode& mode) {
 }
 
 std::ostream& operator<<(std::ostream& os, const DlColor& color) {
-  return os << "DlColor(" << std::hex << color.argb() << std::dec << ")";
+  const char* color_space;
+  switch(color.getColorSpace()) {
+    case flutter::DlColorSpace::kSRGB:
+      color_space = "srgb";
+      break;
+    case flutter::DlColorSpace::kExtendedSRGB:
+      color_space = "srgb_xr";
+      break;
+    case flutter::DlColorSpace::kDisplayP3:
+      color_space = "p3";
+      break;
+  }
+  return os << "DlColor(" << //
+    color.getAlphaF() << ", " << //
+    color.getRedF() << ", " << //
+    color.getGreenF() << ", " << //
+    color.getBlueF() << ", " << //
+    color_space << ")";
 }
 
 std::ostream& operator<<(std::ostream& os, DlImageSampling sampling) {