1 files changed, 113 insertions, 0 deletions
diff --git a/libs/hwui/CanvasTransform.cpp b/libs/hwui/CanvasTransform.cpp
new file mode 100644
index 000000000000..bac7a4d17a49
--- /dev/null
+++ b/libs/hwui/CanvasTransform.cpp
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "CanvasTransform.h"
+#include "Properties.h"
+
+#include <SkColorFilter.h>
+#include <SkPaint.h>
+#include <log/log.h>
+
+namespace android::uirenderer {
+
+static SkColor makeLight(SkColor color) {
+    SkScalar hsv[3];
+    SkColorToHSV(color, hsv);
+    if (hsv[1] > .2f) return color;
+    // hsv[1] *= .85f;
+    // hsv[2] = std::min(1.0f, std::max(hsv[2], 1 - hsv[2]) * 1.3f);
+    hsv[2] = std::max(hsv[2], 1.1f - hsv[2]);
+    return SkHSVToColor(SkColorGetA(color), hsv);
+}
+
+static SkColor makeDark(SkColor color) {
+    SkScalar hsv[3];
+    SkColorToHSV(color, hsv);
+    if (hsv[1] > .2f) return color;
+    // hsv[1] *= .85f;
+    // hsv[2] = std::max(0.0f, std::min(hsv[2], 1 - hsv[2]) * .7f);
+    hsv[2] = std::min(hsv[2], 1.1f - hsv[2]);
+    return SkHSVToColor(SkColorGetA(color), hsv);
+}
+
+static SkColor transformColor(ColorTransform transform, SkColor color) {
+    switch (transform) {
+        case ColorTransform::Light:
+            return makeLight(color);
+        case ColorTransform::Dark:
+            return makeDark(color);
+        default:
+            return color;
+    }
+}
+
+static void applyColorTransform(ColorTransform transform, SkPaint& paint) {
+    if (transform == ColorTransform::None) return;
+
+    SkColor newColor = transformColor(transform, paint.getColor());
+    paint.setColor(newColor);
+
+    if (paint.getColorFilter()) {
+        SkBlendMode mode;
+        SkColor color;
+        // TODO: LRU this or something to avoid spamming new color mode filters
+        if (paint.getColorFilter()->asColorMode(&color, &mode)) {
+            color = transformColor(transform, color);
+            paint.setColorFilter(SkColorFilter::MakeModeFilter(color, mode));
+        }
+    }
+}
+
+class ColorFilterCanvas : public SkPaintFilterCanvas {
+public:
+    ColorFilterCanvas(ColorTransform transform, SkCanvas* canvas)
+            : SkPaintFilterCanvas(canvas), mTransform(transform) {}
+
+    bool onFilter(SkTCopyOnFirstWrite<SkPaint>* paint, Type type) const override {
+        if (*paint) {
+            applyColorTransform(mTransform, *(paint->writable()));
+        }
+        return true;
+    }
+
+private:
+    ColorTransform mTransform;
+};
+
+std::unique_ptr<SkCanvas> makeTransformCanvas(SkCanvas* inCanvas, ColorTransform transform) {
+    switch (transform) {
+        case ColorTransform::Light:
+            return std::make_unique<ColorFilterCanvas>(ColorTransform::Light, inCanvas);
+        case ColorTransform::Dark:
+            return std::make_unique<ColorFilterCanvas>(ColorTransform::Dark, inCanvas);
+        default:
+            return nullptr;
+    }
+}
+
+std::unique_ptr<SkCanvas> makeTransformCanvas(SkCanvas* inCanvas, UsageHint usageHint) {
+    if (Properties::forceDarkMode) {
+        switch (usageHint) {
+            case UsageHint::Unknown:
+                return makeTransformCanvas(inCanvas, ColorTransform::Light);
+            case UsageHint::Background:
+                return makeTransformCanvas(inCanvas, ColorTransform::Dark);
+        }
+    }
+    return nullptr;
+}
+
+};  // namespace android::uirenderer
+\ No newline at end of file