Add blending option to use blend factor from the spine file

defold-spine/commonsrc/spine_ddf.proto

@@ -22,6 +22,7 @@ message SpineModelDesc
         BLEND_MODE_ADD       = 1 [(displayName) = "Add"];
         BLEND_MODE_MULT      = 3 [(displayName) = "Multiply"];
         BLEND_MODE_SCREEN    = 4 [(displayName) = "Screen"];
+        BLEND_MODE_INHERIT   = 5 [(displayName) = "Inherit"];
     }
 
     required string spine_scene         = 1 [(resource)=true];

defold-spine/commonsrc/vertices.cpp

@@ -143,8 +143,23 @@ uint32_t CalcVertexBufferSize(const spSkeleton* skeleton, uint32_t* out_max_tria
     return count;
 }
 
+uint32_t CalcDrawDescCount(const spSkeleton* skeleton)
+{
+    uint32_t count = 0;
+    for (int s = 0; s < skeleton->slotsCount; ++s)
+    {
+        spSlot* slot = skeleton->drawOrder[s];
+        spAttachment* attachment = slot->attachment;
+        if (!attachment)
+        {
+            continue;
+        }
+        count++;
+    }
+    return count;
+}
 
-uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleton* skeleton, const dmVMath::Matrix4& world)
+uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleton* skeleton, const dmVMath::Matrix4& world, dmArray<SpineDrawDesc>* draw_descs_out)
 {
     dmArray<float> scratch; // scratch buffer
 
@@ -170,28 +185,7 @@ uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleto
             continue;
         }
 
-        // We let the user override the blend mode for the whole spine scene at the .spinemodel level
-        // // Fetch the blend mode from the slot and
-        // // translate it to the engine blend mode
-        // BlendMode engineBlendMode;
-        // switch (slot->data->blendMode) {
-        //    case SP_BLEND_MODE_NORMAL:
-        //       engineBlendMode = BLEND_NORMAL;
-        //       break;
-        //    case SP_BLEND_MODE_ADDITIVE:
-        //       engineBlendMode = BLEND_ADDITIVE;
-        //       break;
-        //    case SP_BLEND_MODE_MULTIPLY:
-        //       engineBlendMode = BLEND_MULTIPLY;
-        //       break;
-        //    case SP_BLEND_MODE_SCREEN:
-        //       engineBlendMode = BLEND_SCREEN;
-        //       break;
-        //    default:
-        //       // unknown Spine blend mode, fall back to
-        //       // normal blend mode
-        //       engineBlendMode = BLEND_NORMAL;
-        // }
+        uint32_t batch_vindex_start = vindex;
 
         // Calculate the tinting color based on the skeleton's color
         // and the slot's color. Each color channel is given in the
@@ -271,6 +265,15 @@ uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleto
                 addVertex(&vertex_buffer[vindex++], scratch[index], scratch[index + 1], uvs[index], uvs[index + 1], colorR, colorG, colorB, colorA, page_index);
             }
         }
+
+        if (draw_descs_out)
+        {
+            SpineDrawDesc desc;
+            desc.m_VertexStart = batch_vindex_start;
+            desc.m_BlendMode   = (uint32_t) slot->data->blendMode;
+            desc.m_VertexCount = vindex - batch_vindex_start;
+            draw_descs_out->Push(desc);
+        }
     }
     scratch.SetSize(0);
 
@@ -295,4 +298,30 @@ uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleto
     return vcount;
 }
 
+void MergeDrawDescs(const dmArray<SpineDrawDesc>& src, dmArray<SpineDrawDesc>& dst)
+{
+    dst.SetCapacity(src.Size());
+    dst.SetSize(src.Size());
+
+    SpineDrawDesc* current_draw_desc = dst.Begin();
+    *current_draw_desc = src[0];
+
+    // If we are using "inherit" blending mode, we need to produce render objects based
+    // on the blend mode. If two consecutive draws have the same blend mode, we can merge them.
+    for (int i = 1; i < src.Size(); ++i)
+    {
+        if (current_draw_desc->m_BlendMode == src[i].m_BlendMode)
+        {
+            current_draw_desc->m_VertexCount += src[i].m_VertexCount;
+        }
+        else
+        {
+            current_draw_desc++;
+            *current_draw_desc = src[i];
+        }
+    }
+    uint32_t trimmed_size = current_draw_desc - dst.Begin() + 1;
+    dst.SetSize(trimmed_size);
+}
+
 } // dmSpine

defold-spine/editor/src/spineext.clj

@@ -346,9 +346,22 @@
 (defn- set-constants! [^GL2 gl shader ro]
   (doall (map (fn [constant] (set-constant! gl shader constant)) (.m_Constants ro))))
 
+(defn- blend-factor-value-to-blend-mode [blend-factor-value]
+  (case blend-factor-value
+    0 :blend-mode-alpha
+    1 :blend-mode-add
+    2 :blend-mode-mult
+    3 :blend-mode-screen
+    :blend-mode-alpha))
+
 (defn- do-render-object! [^GL2 gl render-args shader renderable ro]
   (let [start (.m_VertexStart ro) ; the name is from the engine, but in this case refers to the index
         count (.m_VertexCount ro)
+        renderable-user-data (:user-data renderable)
+        renderable-blend-mode (:blend-mode renderable-user-data)
+        blend-mode (if (= renderable-blend-mode :blend-mode-inherit)
+                     (blend-factor-value-to-blend-mode (.m_BlendFactor ro))
+                     renderable-blend-mode)
         face-winding (if (not= (.m_FaceWindingCCW ro) 0) GL/GL_CCW GL/GL_CW)
         _ (set-constants! gl shader ro)
         ro-transform (double-array (.m (.m_WorldTransform ro)))
@@ -363,7 +376,7 @@
                                                           (:view render-args)
                                                           (:projection render-args)
                                                           (:texture render-args)))]
-
+    (gl/set-blend-mode gl blend-mode)
     (shader/set-uniform shader gl "world_view_proj" (:world-view-proj render-args))
     (when (not= (.m_SetFaceWinding ro) 0)
       (gl/gl-front-face gl face-winding))
@@ -373,8 +386,7 @@
       (gl/gl-draw-arrays gl triangle-mode start count))
     (when use-index-buffer
       (gl/gl-draw-elements gl triangle-mode start count))
-    ; reset blend state
-    (.glBlendFunc gl GL/GL_SRC_ALPHA GL/GL_ONE_MINUS_SRC_ALPHA)))
+    (gl/set-blend-mode gl :blend-mode-alpha)))
 
 (set! *warn-on-reflection* true)
 
@@ -391,15 +403,13 @@
 (defn- render-group-transparent [^GL2 gl render-args override-shader group]
   (let [renderable (:renderable group)
         user-data (:user-data renderable)
-        blend-mode (:blend-mode user-data)
         gpu-texture (or (get user-data :gpu-texture) texture/white-pixel)
         shader (if (not= override-shader nil) override-shader (:shader user-data))
         vb (:vertex-buffer group)
         render-objects (:render-objects group)
         vertex-binding (vtx/use-with ::spine-trans vb shader)]
     (gl/with-gl-bindings gl render-args [gpu-texture shader vertex-binding]
       (setup-gl gl)
-      (gl/set-blend-mode gl blend-mode)
       (doall (map (fn [ro] (do-render-object! gl render-args shader renderable ro)) render-objects))
       (restore-gl gl))))
 
@@ -428,20 +438,19 @@
 
 (g/defnk produce-main-scene [_node-id aabb material-shader gpu-texture default-tex-params aabb spine-scene-pb spine-data-handle]
   (when (and gpu-texture)
-    (let [blend-mode :blend-mode-alpha]
-      (assoc {:node-id _node-id :aabb aabb}
-             :renderable {:render-fn render-spine-scenes
-                          :tags #{:spine}
-                          :batch-key [gpu-texture material-shader]
-                          :select-batch-key _node-id
-                          :user-data {:aabb aabb
-                                      :spine-scene-pb spine-scene-pb
-                                      :spine-data-handle spine-data-handle
-                                      :shader material-shader
-                                      :gpu-texture gpu-texture
-                                      :tex-params default-tex-params
-                                      :blend-mode blend-mode}
-                          :passes [pass/transparent pass/selection]}))))
+    (assoc {:node-id _node-id :aabb aabb}
+           :renderable {:render-fn render-spine-scenes
+                        :tags #{:spine}
+                        :batch-key [gpu-texture material-shader]
+                        :select-batch-key _node-id
+                        :user-data {:aabb aabb
+                                    :spine-scene-pb spine-scene-pb
+                                    :spine-data-handle spine-data-handle
+                                    :shader material-shader
+                                    :gpu-texture gpu-texture
+                                    :tex-params default-tex-params
+                                    :blend-mode :blend-mode-alpha}
+                        :passes [pass/transparent pass/selection]})))
 
 (defn- make-spine-outline-scene [_node-id aabb]
   {:aabb aabb
@@ -776,7 +785,7 @@
 
 ;;//////////////////////////////////////////////////////////////////////////////////////////////
 
-(g/defnk produce-model-pb [spine-scene-resource default-animation skin material-resource blend-mode create-go-bones playback-rate offset]
+(g/defnk produce-model-pb [spine-scene-resource blend-mode default-animation skin material-resource create-go-bones playback-rate offset]
   (cond-> {:spine-scene (resource/resource->proj-path spine-scene-resource)
            :default-animation default-animation
            :skin skin
@@ -953,13 +962,14 @@
 
   (output updatable g/Any :cached produce-spine-data-handle-updatable)
 
-  (output scene g/Any :cached (g/fnk [_node-id spine-main-scene aabb material-shader tex-params spine-data-handle default-animation skin updatable]
+  (output scene g/Any :cached (g/fnk [_node-id spine-main-scene aabb blend-mode material-shader tex-params spine-data-handle default-animation skin updatable]
                                      (if (and (some? material-shader) (some? (:renderable spine-main-scene)))
                                        (let [aabb aabb
                                              spine-scene-node-id (:node-id spine-main-scene)]
                                          (-> spine-main-scene
                                              (assoc-in [:renderable :user-data :shader] material-shader)
                                              (update-in [:renderable :user-data :gpu-texture] texture/set-params tex-params)
+                                             (assoc-in [:renderable :user-data :blend-mode] blend-mode)
                                              (assoc-in [:renderable :user-data :skin] skin)
                                              (assoc-in [:renderable :user-data :animation] default-animation)
                                              (assoc-in [:renderable :user-data :spine-data-handle] spine-data-handle)

defold-spine/include/common/vertices.h

@@ -7,7 +7,6 @@
 
 struct spSkeleton;
 
-
 namespace dmSpine
 {
 
@@ -27,8 +26,17 @@ struct SpineModelBounds
     float maxY;
 };
 
+struct SpineDrawDesc
+{
+    uint32_t m_VertexStart;
+    uint32_t m_VertexCount;
+    uint32_t m_BlendMode; // spBlendMode
+};
+
 uint32_t CalcVertexBufferSize(const spSkeleton* skeleton, uint32_t* out_max_triangle_count);
-uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleton* skeleton, const dmVMath::Matrix4& world);
+uint32_t CalcDrawDescCount(const spSkeleton* skeleton);
+uint32_t GenerateVertexData(dmArray<SpineVertex>& vertex_buffer, const spSkeleton* skeleton, const dmVMath::Matrix4& world, dmArray<SpineDrawDesc>* draw_descs);
 void GetSkeletonBounds(const spSkeleton* skeleton, SpineModelBounds& bounds);
+void MergeDrawDescs(const dmArray<SpineDrawDesc>& src, dmArray<SpineDrawDesc>& dst);
 
 } // dmSpine

defold-spine/pluginsrc/com/defold/bob/pipeline/Spine.java

@@ -256,7 +256,7 @@ static public class RenderObject extends Structure {
         public int                  m_NumConstants;
         public int                  m_VertexStart;
         public int                  m_VertexCount;
-        public int                  pad1;
+        public int                  m_BlendFactor;
         public byte                 m_SetBlendFactors;
         public byte                 m_SetStencilTest;
         public byte                 m_SetFaceWinding;
@@ -268,7 +268,7 @@ static public class RenderObject extends Structure {
         protected List getFieldOrder() {
             return Arrays.asList(new String[] {
                 "m_StencilTestParams", "m_WorldTransform", "m_Constants",
-                "m_NumConstants", "m_VertexStart", "m_VertexCount", "pad1",
+                "m_NumConstants", "m_VertexStart", "m_VertexCount", "m_BlendFactor",
                 "m_SetBlendFactors", "m_SetStencilTest", "m_SetFaceWinding", "m_FaceWindingCCW", "m_UseIndexBuffer", "m_IsTriangleStrip", "pad2"});
         }
 

defold-spine/pluginsrc/plugin.cpp

@@ -676,24 +676,35 @@ static void UpdateRenderData(SpineFile* file)
     file->m_RenderObjects.SetSize(0);
     file->m_VertexBuffer.SetSize(0);
 
-    uint32_t ro_count = 1;
+    uint32_t ro_count = dmSpine::CalcDrawDescCount(file->m_SkeletonInstance);
     AdjustArraySize(file->m_RenderObjects, ro_count);
 
+    dmArray<dmSpine::SpineDrawDesc> draw_descs;
+    draw_descs.SetCapacity(ro_count);
+
     dmVMath::Matrix4 transform = dmVMath::Matrix4::identity();
-    dmSpine::GenerateVertexData(file->m_VertexBuffer, file->m_SkeletonInstance, transform);
+    dmSpine::GenerateVertexData(file->m_VertexBuffer, file->m_SkeletonInstance, transform, &draw_descs);
+
+    dmArray<dmSpine::SpineDrawDesc> merged_draw_descs;
+    MergeDrawDescs(draw_descs, merged_draw_descs);
 
-    dmSpinePlugin::RenderObject& ro = file->m_RenderObjects[0];
-    ro.Init();
-    ro.m_VertexStart       = 0; // byte offset
-    ro.m_VertexCount       = file->m_VertexBuffer.Size();
-    ro.m_SetStencilTest    = 0;
-    ro.m_UseIndexBuffer    = 0;
-    ro.m_IsTriangleStrip   = 0; // 0 == GL_TRIANGLES, 1 == GL_TRIANGLE_STRIP
+    file->m_RenderObjects.SetSize(merged_draw_descs.Size());
 
-    ro.m_SetFaceWinding    = 0;
-    ro.m_FaceWindingCCW    = dmGraphics::FACE_WINDING_CCW;
+    for (int i = 0; i < merged_draw_descs.Size(); ++i)
+    {
+        dmSpinePlugin::RenderObject& ro = file->m_RenderObjects[i];
+        ro.Init();
+        ro.m_VertexStart       = merged_draw_descs[i].m_VertexStart; // byte offset
+        ro.m_VertexCount       = merged_draw_descs[i].m_VertexCount;
+        ro.m_SetStencilTest    = 0;
+        ro.m_UseIndexBuffer    = 0;
+        ro.m_IsTriangleStrip   = 0; // 0 == GL_TRIANGLES, 1 == GL_TRIANGLE_STRIP
+        ro.m_BlendFactor       = merged_draw_descs[i].m_BlendMode;
+        ro.m_SetFaceWinding    = 0;
+        ro.m_FaceWindingCCW    = dmGraphics::FACE_WINDING_CCW;
 
-    //ro.AddConstant(UNIFORM_TINT, dmVMath::Vector4(1.0f, 1.0f, 1.0f, 1.0f));
+        //ro.AddConstant(UNIFORM_TINT, dmVMath::Vector4(1.0f, 1.0f, 1.0f, 1.0f));
 
-    ro.m_WorldTransform = transform;
+        ro.m_WorldTransform = transform;
+    }
 }

defold-spine/pluginsrc/renderobject.h

@@ -64,7 +64,7 @@ namespace dmSpinePlugin
         uint32_t                        m_NumConstants;
         uint32_t                        m_VertexStart;
         uint32_t                        m_VertexCount;
-        uint32_t                        : 32;
+        uint32_t                        m_BlendFactor;
 
         bool                            m_SetBlendFactors;
         bool                            m_SetStencilTest;