[core] Add stretches and content to style::Image

4 files changed, 83 insertions, 14 deletions

diff --git a/src/mbgl/sprite/sprite_parser.cpp b/src/mbgl/sprite/sprite_parser.cpp
index 99e2b0c8ca..f141037bc7 100644
--- a/src/mbgl/sprite/sprite_parser.cpp
+++ b/src/mbgl/sprite/sprite_parser.cpp
@@ -25,7 +25,7 @@ std::unique_ptr<style::Image> createStyleImage(const std::string& id,
         ratio <= 0 || ratio > 10 ||
         srcX >= image.size.width || srcY >= image.size.height ||
         srcX + width > image.size.width || srcY + height > image.size.height) {
-        Log::Error(Event::Sprite, "Can't create sprite with invalid metrics: %ux%u@%u,%u in %ux%u@%sx sprite",
+        Log::Error(Event::Sprite, "Can't create image with invalid metrics: %ux%u@%u,%u in %ux%u@%sx sprite",
             width, height, srcX, srcY,
             image.size.width, image.size.height,
             util::toString(ratio).c_str());
diff --git a/src/mbgl/style/image.cpp b/src/mbgl/style/image.cpp
index 1747de5fcc..269f5f9d1a 100644
--- a/src/mbgl/style/image.cpp
+++ b/src/mbgl/style/image.cpp
@@ -6,11 +6,14 @@ namespace mbgl {
 namespace style {
 
 Image::Image(std::string id,
-             PremultipliedImage &&image,
+             PremultipliedImage&& image,
              const float pixelRatio,
-             bool sdf)
-    : baseImpl(makeMutable<Impl>(std::move(id), std::move(image), pixelRatio, sdf)) {
-}
+             bool sdf,
+             ImageStretches stretchX,
+             ImageStretches stretchY,
+             optional<ImageContent> content)
+    : baseImpl(makeMutable<Impl>(
+          std::move(id), std::move(image), pixelRatio, sdf, std::move(stretchX), std::move(stretchY), content)) {}
 
 std::string Image::getID() const {
     return baseImpl->id;
@@ -30,5 +33,17 @@ float Image::getPixelRatio() const {
     return baseImpl->pixelRatio;
 }
 
+const ImageStretches& Image::getStretchX() const {
+    return baseImpl->stretchX;
+}
+
+const ImageStretches& Image::getStretchY() const {
+    return baseImpl->stretchY;
+}
+
+const ImageContent& Image::getContent() const {
+    return baseImpl->content;
+}
+
 } // namespace style
 } // namespace mbgl
diff --git a/src/mbgl/style/image_impl.cpp b/src/mbgl/style/image_impl.cpp
index ce327262e8..c43bb552ee 100644
--- a/src/mbgl/style/image_impl.cpp
+++ b/src/mbgl/style/image_impl.cpp
@@ -4,19 +4,60 @@
 namespace mbgl {
 namespace style {
 
+namespace {
+
+bool validateStretch(const ImageStretches& stretches, const float size) {
+    if (stretches.empty()) {
+        return true;
+    }
+    float last = 0;
+    for (auto& part : stretches) {
+        if (part.first < last || part.second < part.first || size < part.second) {
+            return false;
+        }
+        last = part.second;
+    }
+    return true;
+}
+
+bool validateContent(const ImageContent& content, const Size& size) {
+    if (content.left < 0 || size.width < content.left) return false;
+    if (content.top < 0 || size.height < content.top) return false;
+    if (content.right < 0 || size.width < content.right) return false;
+    if (content.bottom < 0 || size.height < content.bottom) return false;
+    if (content.right < content.left) return false;
+    if (content.bottom < content.top) return false;
+    return true;
+}
+
+} // namespace
+
 Image::Impl::Impl(std::string id_,
                   PremultipliedImage&& image_,
                   const float pixelRatio_,
-                  bool sdf_)
-        : id(std::move(id_)),
-          image(std::move(image_)),
-          pixelRatio(pixelRatio_),
-          sdf(sdf_) {
-
+                  bool sdf_,
+                  ImageStretches stretchX_,
+                  ImageStretches stretchY_,
+                  optional<ImageContent> content_)
+    : id(std::move(id_)),
+      image(std::move(image_)),
+      pixelRatio(pixelRatio_),
+      sdf(sdf_),
+      stretchX(std::move(stretchX_)),
+      stretchY(std::move(stretchY_)),
+      content(content_
+                  ? std::move(*content_)
+                  : ImageContent{0, 0, static_cast<float>(image.size.width), static_cast<float>(image.size.height)}) {
     if (!image.valid()) {
-        throw util::SpriteImageException("Sprite image dimensions may not be zero");
+        throw util::StyleImageException("dimensions may not be zero");
     } else if (pixelRatio <= 0) {
-        throw util::SpriteImageException("Sprite pixelRatio may not be <= 0");
+        throw util::StyleImageException("pixelRatio may not be <= 0");
+    } else if (!validateStretch(stretchX, image.size.width)) {
+        throw util::StyleImageException("stretchX is out of bounds or overlapping");
+    } else if (!validateStretch(stretchY, image.size.height)) {
+        throw util::StyleImageException("stretchY is out of bounds or overlapping");
+    } else if (!validateContent(content, image.size)) {
+        throw util::StyleImageException("content area is invalid");
     }
 }
 
diff --git a/src/mbgl/style/image_impl.hpp b/src/mbgl/style/image_impl.hpp
index b2decbf781..683cd3347b 100644
--- a/src/mbgl/style/image_impl.hpp
+++ b/src/mbgl/style/image_impl.hpp
@@ -11,7 +11,13 @@ namespace style {
 
 class Image::Impl {
 public:
-    Impl(std::string id, PremultipliedImage&&, float pixelRatio, bool sdf = false);
+    Impl(std::string id,
+         PremultipliedImage&&,
+         float pixelRatio,
+         bool sdf = false,
+         ImageStretches stretchX = {},
+         ImageStretches stretchY = {},
+         optional<ImageContent> content = nullopt);
 
     const std::string id;
 
@@ -22,6 +28,13 @@ public:
 
     // Whether this image should be interpreted as a signed distance field icon.
     const bool sdf;
+
+    // Stretch areas of this image.
+    const ImageStretches stretchX;
+    const ImageStretches stretchY;
+
+    // The space where text can be fit into this image.
+    const ImageContent content;
 };
 
 } // namespace style