[core][ios][android][macos] Use premultiplied image directly for RasterTile and ImageSource, un-premultiply in the shader for blending

15 files changed, 53 insertions, 34 deletions

diff --git a/include/mbgl/style/sources/image_source.hpp b/include/mbgl/style/sources/image_source.hpp
index d8a2c45bd8..009764291f 100644
--- a/include/mbgl/style/sources/image_source.hpp
+++ b/include/mbgl/style/sources/image_source.hpp
@@ -18,7 +18,7 @@ public:
     optional<std::string> getURL() const;
     void setURL(const std::string& url);
 
-    void setImage(UnassociatedImage&&);
+    void setImage(PremultipliedImage&&);
 
     void setCoordinates(const std::array<LatLng, 4>&);
     std::array<LatLng, 4> getCoordinates() const;
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/AnimatedImageSourceActivity.java b/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/AnimatedImageSourceActivity.java
index aeb6751b99..1beba632b0 100644
--- a/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/AnimatedImageSourceActivity.java
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/AnimatedImageSourceActivity.java
@@ -1,10 +1,16 @@
 package com.mapbox.mapboxsdk.testapp.activity.style;
 
+import android.content.Context;
+import android.graphics.Bitmap;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Handler;
 import android.support.annotation.NonNull;
+import android.support.v4.content.ContextCompat;
 import android.support.v7.app.AppCompatActivity;
 
+import com.mapbox.mapboxsdk.Mapbox;
 import com.mapbox.mapboxsdk.geometry.LatLng;
 import com.mapbox.mapboxsdk.geometry.LatLngQuad;
 import com.mapbox.mapboxsdk.maps.MapView;
@@ -106,17 +112,27 @@ public class AnimatedImageSourceActivity extends AppCompatActivity implements On
 
     private MapboxMap mapboxMap;
     private Handler handler;
-    private int[] drawables;
+    private Bitmap[] drawables;
     private int drawableIndex;
 
+    Bitmap getBitmap(int resourceId) {
+      Context context = Mapbox.getApplicationContext();
+      Drawable drawable = ContextCompat.getDrawable(context, resourceId);
+      if (drawable instanceof BitmapDrawable) {
+        BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
+        return bitmapDrawable.getBitmap();
+      }
+      return null;
+    }
+
     RefreshImageRunnable(MapboxMap mapboxMap, Handler handler) {
       this.mapboxMap = mapboxMap;
       this.handler = handler;
-      drawables = new int[4];
-      drawables[0] = R.drawable.southeast_radar_0;
-      drawables[1] = R.drawable.southeast_radar_1;
-      drawables[2] = R.drawable.southeast_radar_2;
-      drawables[3] = R.drawable.southeast_radar_3;
+      drawables = new Bitmap[4];
+      drawables[0] = getBitmap(R.drawable.southeast_radar_0);
+      drawables[1] = getBitmap(R.drawable.southeast_radar_1);
+      drawables[2] = getBitmap(R.drawable.southeast_radar_2);
+      drawables[3] = getBitmap(R.drawable.southeast_radar_3);
       drawableIndex = 1;
     }
 
diff --git a/platform/android/src/style/sources/image_source.cpp b/platform/android/src/style/sources/image_source.cpp
index cc7e1e7404..9c37d63d4b 100644
--- a/platform/android/src/style/sources/image_source.cpp
+++ b/platform/android/src/style/sources/image_source.cpp
@@ -40,8 +40,7 @@ namespace android {
     }
 
     void ImageSource::setImage(jni::JNIEnv& env, jni::Object<Bitmap> bitmap) {
-        UnassociatedImage image = util::unpremultiply(Bitmap::GetImage(env, bitmap));
-        source.as<mbgl::style::ImageSource>()->setImage(std:: move(image));
+        source.as<mbgl::style::ImageSource>()->setImage(Bitmap::GetImage(env, bitmap));
     }
 
     jni::Class<ImageSource> ImageSource::javaClass;
diff --git a/platform/darwin/src/MGLImageSource.mm b/platform/darwin/src/MGLImageSource.mm
index 0a2dc2713f..351247e901 100644
--- a/platform/darwin/src/MGLImageSource.mm
+++ b/platform/darwin/src/MGLImageSource.mm
@@ -60,10 +60,9 @@
 
 - (void)setImage:(MGLImage *)image {
     if (image != nullptr) {
-        mbgl::UnassociatedImage unassociatedImage = mbgl::util::unpremultiply(image.mgl_premultipliedImage);
-        self.rawSource->setImage(std::move(unassociatedImage));
+        self.rawSource->setImage(image.mgl_premultipliedImage);
     } else {
-        self.rawSource->setImage(mbgl::UnassociatedImage({0,0}));
+        self.rawSource->setImage(mbgl::PremultipliedImage({0,0}));
     }
     _image = image;
 }
diff --git a/src/mbgl/renderer/buckets/raster_bucket.cpp b/src/mbgl/renderer/buckets/raster_bucket.cpp
index 61548ee333..8a2f1227a5 100644
--- a/src/mbgl/renderer/buckets/raster_bucket.cpp
+++ b/src/mbgl/renderer/buckets/raster_bucket.cpp
@@ -9,11 +9,11 @@ namespace mbgl {
 
 using namespace style;
 
-RasterBucket::RasterBucket(UnassociatedImage&& image_) {
-    image = std::make_shared<UnassociatedImage>(std::move(image_));
+RasterBucket::RasterBucket(PremultipliedImage&& image_) {
+    image = std::make_shared<PremultipliedImage>(std::move(image_));
 }
 
-RasterBucket::RasterBucket(std::shared_ptr<UnassociatedImage> image_): image(image_) {
+RasterBucket::RasterBucket(std::shared_ptr<PremultipliedImage> image_): image(image_) {
 
 }
 void RasterBucket::upload(gl::Context& context) {
@@ -40,7 +40,7 @@ void RasterBucket::clear() {
     uploaded = false;
 }
 
-void RasterBucket::setImage(std::shared_ptr<UnassociatedImage> image_) {
+void RasterBucket::setImage(std::shared_ptr<PremultipliedImage> image_) {
     image = std::move(image_);
     texture = {};
     uploaded = false;
diff --git a/src/mbgl/renderer/buckets/raster_bucket.hpp b/src/mbgl/renderer/buckets/raster_bucket.hpp
index e92e4b51f7..1b0d787bcd 100644
--- a/src/mbgl/renderer/buckets/raster_bucket.hpp
+++ b/src/mbgl/renderer/buckets/raster_bucket.hpp
@@ -13,8 +13,8 @@ namespace mbgl {
 
 class RasterBucket : public Bucket {
 public:
-    RasterBucket(UnassociatedImage&&);
-    RasterBucket(std::shared_ptr<UnassociatedImage>);
+    RasterBucket(PremultipliedImage&&);
+    RasterBucket(std::shared_ptr<PremultipliedImage>);
     void upload(gl::Context&) override;
     void render(Painter&, PaintParameters&, const RenderLayer&, const RenderTile&) override;
     void render(Painter& painter,
@@ -24,8 +24,8 @@ public:
     bool hasData() const override;
 
     void clear();
-    void setImage(std::shared_ptr<UnassociatedImage>);
-    std::shared_ptr<UnassociatedImage> image;
+    void setImage(std::shared_ptr<PremultipliedImage>);
+    std::shared_ptr<PremultipliedImage> image;
     optional<gl::Texture> texture;
 
     // Bucket specific vertices are used for Image Sources only
diff --git a/src/mbgl/renderer/sources/render_image_source.cpp b/src/mbgl/renderer/sources/render_image_source.cpp
index a17f97ee2f..3ffff5c8c6 100644
--- a/src/mbgl/renderer/sources/render_image_source.cpp
+++ b/src/mbgl/renderer/sources/render_image_source.cpp
@@ -82,7 +82,7 @@ void RenderImageSource::update(Immutable<style::Source::Impl> baseImpl_,
     std::swap(baseImpl, baseImpl_);
 
     auto coords = impl().getCoordinates();
-    std::shared_ptr<UnassociatedImage> image = impl().getImage();
+    std::shared_ptr<PremultipliedImage> image = impl().getImage();
 
     if (!image || !image->valid()) {
         enabled = false;
diff --git a/src/mbgl/shaders/raster.cpp b/src/mbgl/shaders/raster.cpp
index eb7a2db240..f454078310 100644
--- a/src/mbgl/shaders/raster.cpp
+++ b/src/mbgl/shaders/raster.cpp
@@ -45,6 +45,12 @@ void main() {
     // read and cross-fade colors from the main and parent tiles
     vec4 color0 = texture2D(u_image0, v_pos0);
     vec4 color1 = texture2D(u_image1, v_pos1);
+    if (color0.a > 0.0) {
+        color0.rgb = color0.rgb / color0.a;
+    }
+    if (color1.a > 0.0) {
+        color1.rgb = color1.rgb / color1.a;
+    }
     vec4 color = mix(color0, color1, u_fade_t);
     color.a *= u_opacity;
     vec3 rgb = color.rgb;
diff --git a/src/mbgl/style/sources/image_source.cpp b/src/mbgl/style/sources/image_source.cpp
index 9313d8da4a..9b60ba1a48 100644
--- a/src/mbgl/style/sources/image_source.cpp
+++ b/src/mbgl/style/sources/image_source.cpp
@@ -37,7 +37,7 @@ void ImageSource::setURL(const std::string& url_) {
     }
 }
 
-void ImageSource::setImage(UnassociatedImage&& image_) {
+void ImageSource::setImage(PremultipliedImage&& image_) {
     url = {};
     if (req) {
         req.reset();
@@ -70,8 +70,7 @@ void ImageSource::loadDescription(FileSource& fileSource) {
             observer->onSourceError(*this, std::make_exception_ptr(std::runtime_error("unexpectedly empty image url")));
         } else {
             try {
-                UnassociatedImage image = util::unpremultiply(decodeImage(*res.data));
-                baseImpl = makeMutable<Impl>(impl(), std::move(image));
+                baseImpl = makeMutable<Impl>(impl(), decodeImage(*res.data));
             } catch (...) {
                 observer->onSourceError(*this, std::current_exception());
             }
diff --git a/src/mbgl/style/sources/image_source_impl.cpp b/src/mbgl/style/sources/image_source_impl.cpp
index eb3e2635e5..c1f31dbdc6 100644
--- a/src/mbgl/style/sources/image_source_impl.cpp
+++ b/src/mbgl/style/sources/image_source_impl.cpp
@@ -15,14 +15,14 @@ ImageSource::Impl::Impl(const Impl& other, std::array<LatLng, 4> coords_)
     image(other.image) {
 }
 
-ImageSource::Impl::Impl(const Impl& rhs, UnassociatedImage&& image_)
+ImageSource::Impl::Impl(const Impl& rhs, PremultipliedImage&& image_)
     : Source::Impl(rhs),
     coords(rhs.coords),
-    image(std::make_shared<UnassociatedImage>(std::move(image_))) {
+    image(std::make_shared<PremultipliedImage>(std::move(image_))) {
 }
 ImageSource::Impl::~Impl() = default;
 
-std::shared_ptr<UnassociatedImage> ImageSource::Impl::getImage() const {
+std::shared_ptr<PremultipliedImage> ImageSource::Impl::getImage() const {
     return image;
 }
 
diff --git a/src/mbgl/style/sources/image_source_impl.hpp b/src/mbgl/style/sources/image_source_impl.hpp
index e0999c34a5..1e1b005a32 100644
--- a/src/mbgl/style/sources/image_source_impl.hpp
+++ b/src/mbgl/style/sources/image_source_impl.hpp
@@ -13,17 +13,17 @@ class ImageSource::Impl : public Source::Impl {
 public:
     Impl(std::string id, std::array<LatLng, 4> coords);
     Impl(const Impl& rhs, std::array<LatLng, 4> coords);
-    Impl(const Impl& rhs, UnassociatedImage&& image);
+    Impl(const Impl& rhs, PremultipliedImage&& image);
 
     ~Impl() final;
 
-    std::shared_ptr<UnassociatedImage> getImage() const;
+    std::shared_ptr<PremultipliedImage> getImage() const;
     std::array<LatLng, 4> getCoordinates() const;
 
     optional<std::string> getAttribution() const final;
 private:
     std::array<LatLng, 4> coords;
-    std::shared_ptr<UnassociatedImage> image;
+    std::shared_ptr<PremultipliedImage> image;
 };
 
 } // namespace style
diff --git a/src/mbgl/tile/raster_tile_worker.cpp b/src/mbgl/tile/raster_tile_worker.cpp
index 86fb5f181d..3c8af97b40 100644
--- a/src/mbgl/tile/raster_tile_worker.cpp
+++ b/src/mbgl/tile/raster_tile_worker.cpp
@@ -17,7 +17,7 @@ void RasterTileWorker::parse(std::shared_ptr<const std::string> data) {
     }
 
     try {
-        auto bucket = std::make_unique<RasterBucket>(util::unpremultiply(decodeImage(*data)));
+        auto bucket = std::make_unique<RasterBucket>(decodeImage(*data));
         parent.invoke(&RasterTile::onParsed, std::move(bucket));
     } catch (...) {
         parent.invoke(&RasterTile::onError, std::current_exception());
diff --git a/test/gl/bucket.test.cpp b/test/gl/bucket.test.cpp
index 24bec0bd22..7ff67f40d0 100644
--- a/test/gl/bucket.test.cpp
+++ b/test/gl/bucket.test.cpp
@@ -101,7 +101,7 @@ TEST(Buckets, SymbolBucket) {
 
 TEST(Buckets, RasterBucket) {
     gl::Context context;
-    UnassociatedImage rgba({ 1, 1 });
+    PremultipliedImage rgba({ 1, 1 });
 
     // RasterBucket::hasData() is always true.
     RasterBucket bucket = { std::move(rgba) };
diff --git a/test/style/source.test.cpp b/test/style/source.test.cpp
index d576dc1e4a..8b9cda1db3 100644
--- a/test/style/source.test.cpp
+++ b/test/style/source.test.cpp
@@ -531,7 +531,7 @@ TEST(Source, ImageSourceImageUpdate) {
 
     // Load initial, so the source state will be loaded=true
     source.loadDescription(test.fileSource);
-    UnassociatedImage rgba({ 1, 1 });
+    PremultipliedImage rgba({ 1, 1 });
     rgba.data[0] = 255;
     rgba.data[1] = 254;
     rgba.data[2] = 253;
diff --git a/test/tile/raster_tile.test.cpp b/test/tile/raster_tile.test.cpp
index 025208c331..4680e7f485 100644
--- a/test/tile/raster_tile.test.cpp
+++ b/test/tile/raster_tile.test.cpp
@@ -60,7 +60,7 @@ TEST(RasterTile, onError) {
 TEST(RasterTile, onParsed) {
     RasterTileTest test;
     RasterTile tile(OverscaledTileID(0, 0, 0), test.tileParameters, test.tileset);
-    tile.onParsed(std::make_unique<RasterBucket>(UnassociatedImage{}));
+    tile.onParsed(std::make_unique<RasterBucket>(PremultipliedImage{}));
     EXPECT_TRUE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());