Add: A 32 bpp blitter that uses the animation buffer from the video backend to speed up palette animation.

src/blitter/40bpp_anim.hpp

@@ -0,0 +1,63 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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, version 2.
+ * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file 40bpp_optimized.hpp Optimized 40 bpp blitter. */
+
+#ifndef BLITTER_40BPP_OPTIMIZED_HPP
+#define BLITTER_40BPP_OPTIMIZED_HPP
+
+
+#include "32bpp_optimized.hpp"
+#include "../video/video_driver.hpp"
+
+/** The optimized 40 bpp blitter (for OpenGL video driver). */
+class Blitter_40bppAnim : public Blitter_32bppOptimized {
+public:
+
+	// void *MoveTo(void *video, int x, int y) override;
+	void SetPixel(void *video, int x, int y, uint8 colour) override;
+	void DrawRect(void *video, int width, int height, uint8 colour) override;
+	void CopyFromBuffer(void *video, const void *src, int width, int height) override;
+	void CopyToBuffer(const void *video, void *dst, int width, int height) override;
+	void CopyImageToBuffer(const void *video, void *dst, int width, int height, int dst_pitch) override;
+	void ScrollBuffer(void *video, int &left, int &top, int &width, int &height, int scroll_x, int scroll_y) override;
+	void Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom) override;
+	void DrawColourMappingRect(void *dst, int width, int height, PaletteID pal) override;
+	Sprite *Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator) override;
+	int BufferSize(int width, int height) override;
+	Blitter::PaletteAnimation UsePaletteAnimation() override;
+	bool NeedsAnimationBuffer() override;
+
+	const char *GetName()  override { return "40bpp-anim"; }
+	int GetBytesPerPixel()  override { return 5; }
+
+	template <BlitterMode mode> void Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom);
+
+protected:
+	static inline Colour RealizeBlendedColour(uint8 anim, Colour c)
+	{
+		return anim != 0 ? AdjustBrightness(LookupColourInPalette(anim), GetColourBrightness(c)) : c;
+	}
+
+};
+
+/** Factory for the 40 bpp animated blitter (for OpenGL). */
+class FBlitter_40bppAnim : public BlitterFactory {
+protected:
+	bool IsUsable() const override
+	{
+		return VideoDriver::GetInstance() == nullptr || VideoDriver::GetInstance()->HasAnimBuffer();
+	}
+
+public:
+	FBlitter_40bppAnim() : BlitterFactory("40bpp-anim", "40bpp Animation Blitter (OpenGL)") {}
+	Blitter *CreateInstance() override { return new Blitter_40bppAnim(); }
+};
+
+#endif /* BLITTER_40BPP_OPTIMIZED_HPP */