add flip to AnimationFrameData

Author: jube

include/gf2/core/AnimationData.h

@@ -19,16 +19,27 @@
 
 namespace gf {
 
+  enum class AnimationFrameFlip : uint8_t {
+    Horizontally = 0x01,
+    Vertically = 0x02,
+    Diagonally = 0x04,
+  };
+
+  template<>
+  struct EnableBitmaskOperators<AnimationFrameFlip> : std::true_type {
+  };
+
   struct GF_CORE_API AnimationFrameData {
     uint32_t texture_index = 0;
     RectF texture_region = RectF::from_size({ 0.0f, 0.0f });
     Time duration;
+    Flags<AnimationFrameFlip> flip = None;
   };
 
   template<typename Archive>
   Archive& operator|(Archive& ar, MaybeConst<AnimationFrameData, Archive>& data)
   {
-    return ar | data.texture_index | data.texture_region | data.duration;
+    return ar | data.texture_index | data.texture_region | data.duration | data.flip;
   }
 
   enum class AnimationProperties : uint8_t {
@@ -45,6 +56,7 @@ namespace gf {
     Color color = White;
 
     void add_tileset(uint32_t texture_index, Vec2I layout, Time duration, int32_t frame_count, int32_t frame_offset = 0, int32_t frame_direction = 1);
+    void add_tileset(uint32_t texture_index, Vec2I layout, Time duration, Flags<AnimationFrameFlip> flip, int32_t frame_count, int32_t frame_offset = 0, int32_t frame_direction = 1);
   };
 
   template<typename Archive>

library/core/AnimationData.cc

@@ -6,6 +6,11 @@
 namespace gf {
 
   void AnimationData::add_tileset(uint32_t texture_index, Vec2I layout, Time duration, int32_t frame_count, int32_t frame_offset, int32_t frame_direction)
+  {
+    add_tileset(texture_index, layout, duration, None, frame_count, frame_offset, frame_direction);
+  }
+
+  void AnimationData::add_tileset(uint32_t texture_index, Vec2I layout, Time duration, Flags<AnimationFrameFlip> flip, int32_t frame_count, int32_t frame_offset, int32_t frame_direction)
   {
     int32_t x = frame_offset % layout.w;
     int32_t y = frame_offset / layout.w;
@@ -17,6 +22,7 @@ namespace gf {
       frame.texture_index = texture_index;
       frame.texture_region = RectF::from_position_size(gf::vec(x, y) * size, size);
       frame.duration = duration;
+      frame.flip = flip;
 
       frames.push_back(frame);
 

library/graphics/AnimationRuntime.cc

@@ -35,6 +35,20 @@ namespace gf::details {
       vertices.push_back({ bounds.position_at(Orientation::NorthWest), frame_data.texture_region.position_at(Orientation::NorthWest), color });
       vertices.push_back({ bounds.position_at(Orientation::SouthWest), frame_data.texture_region.position_at(Orientation::SouthWest), color });
 
+      if (frame_data.flip.test(AnimationFrameFlip::Diagonally)) {
+        std::swap(vertices[index + 0].tex_coords, vertices[index + 3].tex_coords);
+      }
+
+      if (frame_data.flip.test(AnimationFrameFlip::Horizontally)) {
+        std::swap(vertices[index + 0].tex_coords, vertices[index + 2].tex_coords);
+        std::swap(vertices[index + 1].tex_coords, vertices[index + 3].tex_coords);
+      }
+
+      if (frame_data.flip.test(AnimationFrameFlip::Vertically)) {
+        std::swap(vertices[index + 0].tex_coords, vertices[index + 1].tex_coords);
+        std::swap(vertices[index + 2].tex_coords, vertices[index + 3].tex_coords);
+      }
+
       // first triangle
       indices.push_back(index);
       indices.push_back(index + 1);