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engines/ags/engine/gfx/gfx_util.h

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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+//=============================================================================
+//
+// Intermediate level drawing utility functions.
+//
+// GfxUtil namespace is meant for intermediate-to-lower level functions, that
+// implement specific conversions, tricks and hacks for drawing bitmaps and
+// geometry.
+// The suggested convention is to add only those functions, that do not require
+// any knowledge of higher-level engine types and objects.
+//
+//=============================================================================
+
+#ifndef AGS_ENGINE_GFX_GFX_UTIL_H
+#define AGS_ENGINE_GFX_GFX_UTIL_H
+
+#include "ags/shared/gfx/bitmap.h"
+#include "ags/shared/gfx/gfx_def.h"
+
+namespace AGS3 {
+namespace AGS {
+namespace Engine {
+
+using Shared::Bitmap;
+
+namespace GfxUtil {
+// Creates a COPY of the source bitmap, converted to the given format.
+// Keeps mask pixels intact, only converting mask color value if necessary.
+Bitmap *ConvertBitmap(Bitmap *src, int dst_color_depth);
+
+// Considers the given information about source and destination surfaces,
+// then draws a bimtap over another either using requested blending mode,
+// or fallbacks to common "magic pink" transparency mode;
+// optionally uses blending alpha (overall image transparency).
+void DrawSpriteBlend(Bitmap *ds, const Point &ds_at, Bitmap *sprite,
+                     Shared::BlendMode blend_mode, bool dst_has_alpha = true, bool src_has_alpha = true, int blend_alpha = 0xFF);
+
+// Draws a bitmap over another one with given alpha level (0 - 255),
+// takes account of the bitmap's mask color,
+// ignores image's alpha channel, even if there's one;
+// does a conversion if sprite and destination color depths do not match.
+void DrawSpriteWithTransparency(Bitmap *ds, Bitmap *sprite, int x, int y, int alpha = 0xFF);
+} // namespace GfxUtil
+
+} // namespace Engine
+} // namespace AGS
+} // namespace AGS3
+
+#endif