First attempt at re-calculating all colors in a group hierarchy when one color changes, and also protecting user-defined colors.

abase-commands.lua

@@ -8,9 +8,9 @@ local function ExportSpritesheetAdvanced()
 
     local spr = Sprite(app.sprite)
 
-    sprt.deleteLayers(spr, spr.layers)
-    sprt.flattenLayers(spr.layers)
-    sprt.revealLayers(spr.layers)
+    sprt.DeleteLayers(spr, spr.layers)
+    sprt.FlattenLayers(spr.layers)
+    sprt.RevealLayers(spr.layers)
 
     app.command.ExportSpriteSheet {
         splitLayers = true
@@ -26,7 +26,7 @@ local function ToggleIgnore()
     else
         layer.properties(extKey).ignored = true
     end
-    sprt.setColor(layer)
+    sprt.SetColorFromRoot(layer)
 end
 
 local function ToggleExportAsSprite()
@@ -36,7 +36,7 @@ local function ToggleExportAsSprite()
     else
         layer.properties(extKey).exportedAsSprite = true
     end
-    sprt.setColor(layer)
+    sprt.SetColorFromRoot(layer)
 end
 
 local export = {

abase-sprite.lua

@@ -4,40 +4,44 @@ local BASE_COLOR = Color {
     r = 0,
     g = 0,
     b = 0,
-    a = 0
+    a = 0,
 }
 local IGNORE_COLOR = Color {
-    gray = 100
+    gray = 100,
+    alpha = 254,
 }
 local IGNORE_SUBCOLOR = Color {
-    gray = 150
+    gray = 150,
+    alpha = 254,
 }
 local MERGE_COLOR = Color {
     r = 200,
     g = 200,
-    b = 0
+    b = 0,
+    a = 254,
 }
 local MERGE_SUBCOLOR = Color {
     r = 200,
     g = 200,
-    b = 128
+    b = 128,
+    a = 254,
 }
 
 -- Deletes any layers with the 'ignored' property.
-local function deleteLayers(spr, layers)
-    for i, layer in ipairs(layers) do
+local function DeleteLayers(spr, layers)
+    for _, layer in ipairs(layers) do
         if layer.properties(extKey).ignored then
             spr:deleteLayer(layer)
         elseif layer.isGroup then
-            deleteLayers(spr, layer.layers)
+            DeleteLayers(spr, layer.layers)
         end
     end
 end
 
 -- Flattens any layers that have the 'exportedAsSprite' property.
 -- Should be called after deleteLayers.
-local function flattenLayers(layers)
-    for i, layer in ipairs(layers) do
+local function FlattenLayers(layers)
+    for _, layer in ipairs(layers) do
         if not layer.isGroup then
             goto continue
         end
@@ -47,7 +51,7 @@ local function flattenLayers(layers)
             app.command.FlattenLayers(false)
         else
             -- recurse
-            flattenLayers(layer.layers)
+            FlattenLayers(layer.layers)
         end
 
         ::continue::
@@ -56,10 +60,10 @@ end
 
 -- Makes all layers visible.
 -- This should be called after deleteLayers and flattenLayers
-local function revealLayers(layers)
-    for i, layer in ipairs(layers) do
+local function RevealLayers(layers)
+    for _, layer in ipairs(layers) do
         if layer.isGroup then
-            revealLayers(layer.layers)
+            RevealLayers(layer.layers)
         end
 
         if not layer.isVisible then
@@ -68,35 +72,60 @@ local function revealLayers(layers)
     end
 end
 
--- set the color of a layer and its sublayers
-local function setColor(layer, subColor)
+local function safeSetColor(layer, color)
+    pixelValue = layer.color.rgbaPixel
+
+    if (pixelValue ~= BASE_COLOR.rgbaPixel and
+        pixelValue ~= IGNORE_COLOR.rgbaPixel and
+        pixelValue ~= IGNORE_SUBCOLOR.rgbaPixel and
+        pixelValue ~= MERGE_COLOR.rgbaPixel and
+        pixelValue ~= MERGE_SUBCOLOR.rgbaPixel) then
+            print("DEBUG: not setting color")
+            return
+    end
+    layer.color = color
+end
+
+-- set the color of a layer and its sublayers based on the extension properties
+local function SetColor(layer, subColor)
     if (layer.properties(extKey).ignored) then
-        layer.color = IGNORE_COLOR
+        safeSetColor(layer, IGNORE_COLOR)
         subColor = IGNORE_SUBCOLOR
     elseif subColor == IGNORE_SUBCOLOR then
-        layer.color = subColor
+        safeSetColor(layer, subColor)
     elseif (layer.properties(extKey).exportedAsSprite) then
-        layer.color = MERGE_COLOR
+        safeSetColor(layer, MERGE_COLOR)
         subColor = MERGE_SUBCOLOR
     elseif subColor == MERGE_SUBCOLOR then
-        layer.color = subColor
+        safeSetColor(layer, subColor)
     else
-        layer.color = BASE_COLOR
+        safeSetColor(layer, BASE_COLOR)
     end
 
     if (layer.isGroup) then
         for i, sublayer in ipairs(layer.layers) do
-            setColor(sublayer, subColor)
+            SetColor(sublayer, subColor)
         end
     end
 end
 
-
+-- Find the root of the layer stack, then set colors appropriately
+-- for all children
+local function SetColorFromRoot(layer)
+    -- The standard Lua `if table["field"] == nil` throws an error in Aseprite.
+    -- So we just check for the parent Layer being equal to the sprite.
+    if layer.parent == layer.sprite then
+        SetColor(layer)
+    else
+        SetColorFromRoot(layer.parent)
+    end
+end
 
 local export = {
-    deleteLayers = deleteLayers,
-    flattenLayers = flattenLayers,
-    revealLayers = revealLayers,
-    setColor = setColor,
+    DeleteLayers = DeleteLayers,
+    FlattenLayers = FlattenLayers,
+    RevealLayers = RevealLayers,
+    SetColor = SetColor,
+    SetColorFromRoot = SetColorFromRoot,
 }
 return export

readme.md

@@ -19,8 +19,9 @@ To install, go to Aseprite's Settings -> Extensions -> Add Extension, and select
 
 ## Additional Notes
 
-* Toggling the advanced export settings on a layer will modify the layer colors. If you are using layer colors for other purposes, this extension will not work well for you. (This may be configurable in a future update)
 * Ignored layers always take precedence over merging; if a sublayer in a group is ignored, it will not be merged into the final sprite.
+* Toggling the advanced export settings on a layer will modify the layer colors. The extension will attempt to detect and preserve user-colored layers. If you happen to use one of the exact colors we have chosen, this will fail. We have chosen odd alpha values to reduce the likelihood of a false negative, but if you are using layer colors extensively, this extension may not work well for you.
+* To force a layer's color to be controlled by the extension, simply reset the layer's color to all 0 values. (red, green, blue, and alpha should all be 0) You may need to toggle the export settings of a parent layer or create a new layer before the changes take effect.
 
 
 ## Copyright Notice