[lua] Add Image:flip()

src/app/script/engine.cpp

@@ -17,6 +17,7 @@
 #include "app/doc_range.h"
 #include "app/pref/preferences.h"
 #include "app/script/blend_mode.h"
+#include "app/script/flip_type.h"
 #include "app/script/luacpp.h"
 #include "app/script/require.h"
 #include "app/script/security.h"
@@ -449,6 +450,13 @@ Engine::Engine()
   setfield_integer(L, "INTERSECT", (int)gen::SelectionMode::INTERSECT);
   lua_pop(L, 1);
 
+  lua_newtable(L);
+  lua_pushvalue(L, -1);
+  lua_setglobal(L, "FlipType");
+  setfield_integer(L, "HORIZONTAL", app::script::FlipType::HORIZONTAL);
+  setfield_integer(L, "VERTICAL",   app::script::FlipType::VERTICAL);
+  lua_pop(L, 1);
+
   // Register classes/prototypes
   register_brush_class(L);
   register_cel_class(L);

src/app/script/flip_type.h

@@ -0,0 +1,22 @@
+// Aseprite
+// Copyright (c) 2023  Igara Studio S.A.
+//
+// This program is distributed under the terms of
+// the End-User License Agreement for Aseprite.
+
+#ifndef APP_SCRIPT_FLIP_TYPE_H_INCLUDED
+#define APP_SCRIPT_FLIP_TYPE_H_INCLUDED
+#pragma once
+
+namespace app {
+namespace script {
+
+enum class FlipType : int {
+  HORIZONTAL,
+  VERTICAL
+};
+
+} // namespace script
+} // namespace app
+
+#endif

src/app/script/image_class.cpp

@@ -11,6 +11,7 @@
 
 #include "app/cmd/copy_rect.h"
 #include "app/cmd/copy_region.h"
+#include "app/cmd/flip_image.h"
 #include "app/commands/new_params.h" // Used for enum <-> Lua conversions
 #include "app/context.h"
 #include "app/doc.h"
@@ -18,6 +19,7 @@
 #include "app/script/blend_mode.h"
 #include "app/script/docobj.h"
 #include "app/script/engine.h"
+#include "app/script/flip_type.h"
 #include "app/script/luacpp.h"
 #include "app/script/security.h"
 #include "app/site.h"
@@ -578,6 +580,20 @@ int Image_shrinkBounds(lua_State* L)
   return 1;
 }
 
+int Image_flip(lua_State* L)
+{
+  auto obj = get_obj<ImageObj>(L, 1);
+  doc::Image* img = obj->image(L);
+  doc::algorithm::FlipType flipType = doc::algorithm::FlipType::FlipHorizontal;
+  if (lua_isinteger(L, 2) && lua_tointeger(L, 2) > 0)
+    flipType = doc::algorithm::FlipType::FlipVertical;
+
+  Tx tx;
+  tx(new cmd::FlipImage(img, img->bounds(), flipType));
+  tx.commit();
+  return 0;
+}
+
 int Image_get_id(lua_State* L)
 {
   const auto obj = get_obj<ImageObj>(L, 1);
@@ -679,6 +695,7 @@ const luaL_Reg Image_methods[] = {
   { "saveAs", Image_saveAs },
   { "resize", Image_resize },
   { "shrinkBounds", Image_shrinkBounds },
+  { "flip", Image_flip },
   { "__gc", Image_gc },
   { "__eq", Image_eq },
   { nullptr, nullptr }

tests/scripts/image.lua

@@ -403,3 +403,43 @@ do
                       r_255, r_g127, r_g064,
                       r_255, r_255, g_255 })
 end
+
+-- Tests for Image:flip()
+do
+  local img = Image(3, 3)
+  local r = Color(255, 0, 0).rgbaPixel
+  local g = Color(0, 255, 0).rgbaPixel
+  img:clear(0)
+  img:drawPixel(0, 0, g)
+  img:drawPixel(1, 1, r)
+  img:drawPixel(2, 2, r)
+  expect_img(img, { g, 0, 0,
+                    0, r, 0,
+                    0, 0, r })
+  img:flip()
+  expect_img(img, { 0, 0, g,
+                    0, r, 0,
+                    r, 0, 0 })
+  app.undo()
+  expect_img(img, { g, 0, 0,
+                    0, r, 0,
+                    0, 0, r })
+  img:flip(FlipType.HORIZONTAL)
+  expect_img(img, { 0, 0, g,
+                    0, r, 0,
+                    r, 0, 0 })
+  app.undo()
+  img:flip(FlipType.VERTICAL)
+  expect_img(img, { 0, 0, r,
+                    0, r, 0,
+                    g, 0, 0 })
+  img:flip(FlipType.VERTICAL)
+  expect_img(img, { g, 0, 0,
+                    0, r, 0,
+                    0, 0, r })
+  app.undo()
+  app.undo()
+  expect_img(img, { g, 0, 0,
+                    0, r, 0,
+                    0, 0, r })
+end