Improve color blending

Assets/TestScene.unity

@@ -74,56 +74,6 @@ NavMeshSettings:
     widthInaccuracy: 16.666666
     heightInaccuracy: 10
   m_NavMesh: {fileID: 0}
---- !u!1 &1763870612
-GameObject:
-  m_ObjectHideFlags: 0
-  m_PrefabParentObject: {fileID: 0}
-  m_PrefabInternal: {fileID: 0}
-  serializedVersion: 4
-  m_Component:
-  - 4: {fileID: 1763870614}
-  - 212: {fileID: 1763870613}
-  m_Layer: 0
-  m_Name: Pixel Image
-  m_TagString: Untagged
-  m_Icon: {fileID: 0}
-  m_NavMeshLayer: 0
-  m_StaticEditorFlags: 0
-  m_IsActive: 1
---- !u!212 &1763870613
-SpriteRenderer:
-  m_ObjectHideFlags: 0
-  m_PrefabParentObject: {fileID: 0}
-  m_PrefabInternal: {fileID: 0}
-  m_GameObject: {fileID: 1763870612}
-  m_Enabled: 1
-  m_CastShadows: 0
-  m_ReceiveShadows: 0
-  m_LightmapIndex: 255
-  m_LightmapTilingOffset: {x: 1, y: 1, z: 0, w: 0}
-  m_Materials:
-  - {fileID: 10754, guid: 0000000000000000e000000000000000, type: 0}
-  m_SubsetIndices: 
-  m_StaticBatchRoot: {fileID: 0}
-  m_UseLightProbes: 0
-  m_LightProbeAnchor: {fileID: 0}
-  m_ScaleInLightmap: 1
-  m_SortingLayer: 0
-  m_SortingOrder: 0
-  m_SortingLayerID: 0
-  m_Sprite: {fileID: 21300000, guid: e5b83bcc7cf5d1b4a837c63f6def78fe, type: 3}
-  m_Color: {r: 1, g: 1, b: 1, a: 1}
---- !u!4 &1763870614
-Transform:
-  m_ObjectHideFlags: 0
-  m_PrefabParentObject: {fileID: 0}
-  m_PrefabInternal: {fileID: 0}
-  m_GameObject: {fileID: 1763870612}
-  m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
-  m_LocalPosition: {x: .184287488, y: .393926561, z: 0}
-  m_LocalScale: {x: 1, y: 1, z: 1}
-  m_Children: []
-  m_Father: {fileID: 0}
 --- !u!1 &2058043185
 GameObject:
   m_ObjectHideFlags: 0
@@ -191,8 +141,11 @@ Camera:
     m_Bits: 4294967295
   m_RenderingPath: -1
   m_TargetTexture: {fileID: 0}
+  m_TargetDisplay: 0
   m_HDR: 0
   m_OcclusionCulling: 1
+  m_StereoConvergence: 10
+  m_StereoSeparation: .0219999999
 --- !u!4 &2058043190
 Transform:
   m_ObjectHideFlags: 0
@@ -204,3 +157,4 @@ Transform:
   m_LocalScale: {x: 1, y: 1, z: 1}
   m_Children: []
   m_Father: {fileID: 0}
+  m_RootOrder: 0

Assets/UPAToolkit/Editor/UPAImage.cs

@@ -107,14 +107,12 @@ public Color GetBlendedPixel (int x, int y) {
 
 			Color pixel = layers[i].tex.GetPixel(x,y);
 
-			// APPLY THE NORMAL COLOR BLENDING ALGORITHM
+			// This is a blend between two methods of calculating color blending; Alpha blending and premultiplied alpha blending
+			// I have no clue why this actually works but it's very accurate :D
+			float newR = Mathf.Lerp (1f * pixel.r + (1f - pixel.a) * color.r, pixel.a * pixel.r + (1f - pixel.a) * color.r, color.a);
+			float newG = Mathf.Lerp (1f * pixel.g + (1f - pixel.a) * color.g, pixel.a * pixel.g + (1f - pixel.a) * color.g, color.a);
+			float newB = Mathf.Lerp (1f * pixel.b + (1f - pixel.a) * color.b, pixel.a * pixel.b + (1f - pixel.a) * color.b, color.a);
 
-//			float newR = c.a * c.r + (1 - c.a) * bgColor.r;
-//			c0 = Ca * Aa + Cb * Ab * (1 - Aa);
-
-			float newR = pixel.r + color.r * (1 - pixel.a);
-			float newG = pixel.g + color.g * (1 - pixel.a);
-			float newB = pixel.b + color.b * (1 - pixel.a);
 			float newA = pixel.a + color.a * (1 - pixel.a);
 
 			color = new Color (newR, newG, newB, newA);
@@ -132,6 +130,8 @@ public void ChangeLayerPosition (int from, int to) {
 		UPALayer layer = layers[from];
 		layers.RemoveAt(from);
 		layers.Insert(to, layer);
+
+		dirty = true;
 	}
 
 	// Get the rect of the image as displayed in the editor