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

6 files changed, 605 insertions, 2 deletions

diff --git a/src/blitter/32bpp_base.hpp b/src/blitter/32bpp_base.hpp
index f09719450..9d80ec2ce 100644
--- a/src/blitter/32bpp_base.hpp
+++ b/src/blitter/32bpp_base.hpp
@@ -125,6 +125,18 @@ public:
 	}
 
 	/**
+	 * Make a colour dark grey, for specialized 32bpp remapping.
+	 * @param colour the colour to make dark.
+	 * @return the new colour, now darker.
+	 */
+	static inline Colour MakeDark(Colour colour)
+	{
+		uint8 d = MakeDark(colour.r, colour.g, colour.b);
+
+		return Colour(d, d, d);
+	}
+
+	/**
 	 * Make a colour grey - based.
 	 * @param colour the colour to make grey.
 	 * @return the new colour, now grey.
@@ -154,6 +166,16 @@ public:
 
 		return ReallyAdjustBrightness(colour, brightness);
 	}
+
+	static inline uint8 GetColourBrightness(Colour colour)
+	{
+		uint8 rgb_max = std::max(colour.r, std::max(colour.g, colour.b));
+
+		/* Black pixel (8bpp or old 32bpp image), so use default value */
+		if (rgb_max == 0) rgb_max = DEFAULT_BRIGHTNESS;
+
+		return rgb_max;
+	}
 };
 
 #endif /* BLITTER_32BPP_BASE_HPP */
diff --git a/src/blitter/32bpp_optimized.cpp b/src/blitter/32bpp_optimized.cpp
index ad15b8f81..1f8e0bbd2 100644
--- a/src/blitter/32bpp_optimized.cpp
+++ b/src/blitter/32bpp_optimized.cpp
@@ -252,7 +252,7 @@ void Blitter_32bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode,
 	}
 }
 
-Sprite *Blitter_32bppOptimized::Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator)
+template <bool Tpal_to_rgb> Sprite *Blitter_32bppOptimized::EncodeInternal(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator)
 {
 	/* streams of pixels (a, r, g, b channels)
 	 *
@@ -322,7 +322,7 @@ Sprite *Blitter_32bppOptimized::Encode(const SpriteLoader::Sprite *sprite, Alloc
 				if (a != 0) {
 					dst_px->a = a;
 					*dst_n = src->m;
-					if (src->m != 0) {
+					if (Tpal_to_rgb && src->m != 0) {
 						/* Get brightest value */
 						uint8 rgb_max = std::max({src->r, src->g, src->b});
 
@@ -397,3 +397,11 @@ Sprite *Blitter_32bppOptimized::Encode(const SpriteLoader::Sprite *sprite, Alloc
 
 	return dest_sprite;
 }
+
+template Sprite *Blitter_32bppOptimized::EncodeInternal<true>(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator);
+template Sprite *Blitter_32bppOptimized::EncodeInternal<false>(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator);
+
+Sprite *Blitter_32bppOptimized::Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator)
+{
+	return this->EncodeInternal<true>(sprite, allocator);
+}
diff --git a/src/blitter/32bpp_optimized.hpp b/src/blitter/32bpp_optimized.hpp
index a9c732902..9bee600b1 100644
--- a/src/blitter/32bpp_optimized.hpp
+++ b/src/blitter/32bpp_optimized.hpp
@@ -27,6 +27,9 @@ public:
 	const char *GetName() override { return "32bpp-optimized"; }
 
 	template <BlitterMode mode> void Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom);
+
+protected:
+	template <bool Tpal_to_rgb> Sprite *EncodeInternal(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator);
 };
 
 /** Factory for the optimised 32 bpp blitter (without palette animation). */
diff --git a/src/blitter/40bpp_anim.cpp b/src/blitter/40bpp_anim.cpp
new file mode 100644
index 000000000..2cc3be5be
--- /dev/null
+++ b/src/blitter/40bpp_anim.cpp
@@ -0,0 +1,500 @@
+/* $Id$ */
+
+/*
+ * 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.cpp Implementation of the optimized 40 bpp blitter. */
+
+#include "../stdafx.h"
+#include "../zoom_func.h"
+#include "../settings_type.h"
+#include "../video/video_driver.hpp"
+#include "40bpp_anim.hpp"
+
+#include "../table/sprites.h"
+
+#include "../safeguards.h"
+
+
+/** Instantiation of the 40bpp with animation blitter factory. */
+static FBlitter_40bppAnim iFBlitter_40bppAnim;
+
+/** Cached black value. */
+static const Colour _black_colour(0, 0, 0);
+
+
+void Blitter_40bppAnim::SetPixel(void *video, int x, int y, uint8 colour)
+{
+	if (_screen_disable_anim) {
+		Blitter_32bppOptimized::SetPixel(video, x, y, colour);
+	} else {
+		*((Colour *)video + x + y * _screen.pitch) = _black_colour;
+
+		VideoDriver::GetInstance()->GetAnimBuffer()[((uint32 *)video - (uint32 *)_screen.dst_ptr) + x + y * _screen.pitch] = colour;
+	}
+}
+
+void Blitter_40bppAnim::DrawRect(void *video, int width, int height, uint8 colour)
+{
+	if (_screen_disable_anim) {
+		/* This means our output is not to the screen, so we can't be doing any animation stuff, so use our parent DrawRect() */
+		Blitter_32bppOptimized::DrawRect(video, width, height, colour);
+		return;
+	}
+
+	assert(VideoDriver::GetInstance()->GetAnimBuffer() != nullptr);
+	uint8 *anim_line = ((uint32 *)video - (uint32 *)_screen.dst_ptr) + VideoDriver::GetInstance()->GetAnimBuffer();
+
+	do {
+		Colour *dst = (Colour *)video;
+		uint8 *anim = anim_line;
+
+		for (int i = width; i > 0; i--) {
+			*dst = _black_colour;
+			*anim = colour;
+			dst++;
+			anim++;
+		}
+		video = (uint32 *)video + _screen.pitch;
+		anim_line += _screen.pitch;
+	} while (--height);
+}
+
+/**
+ * Draws a sprite to a (screen) buffer. It is templated to allow faster operation.
+ *
+ * @tparam mode blitter mode
+ * @param bp further blitting parameters
+ * @param zoom zoom level at which we are drawing
+ */
+template <BlitterMode mode>
+inline void Blitter_40bppAnim::Draw(const Blitter::BlitterParams *bp, ZoomLevel zoom)
+{
+	const SpriteData *src = (const SpriteData *)bp->sprite;
+
+	/* src_px : each line begins with uint32 n = 'number of bytes in this line',
+	 *          then n times is the Colour struct for this line */
+	const Colour *src_px = (const Colour *)(src->data + src->offset[zoom][0]);
+	/* src_n  : each line begins with uint32 n = 'number of bytes in this line',
+	 *          then interleaved stream of 'm' and 'n' channels. 'm' is remap,
+	 *          'n' is number of bytes with the same alpha channel class */
+	const uint16 *src_n  = (const uint16 *)(src->data + src->offset[zoom][1]);
+
+	/* skip upper lines in src_px and src_n */
+	for (uint i = bp->skip_top; i != 0; i--) {
+		src_px = (const Colour *)((const byte *)src_px + *(const uint32 *)src_px);
+		src_n = (const uint16 *)((const byte *)src_n + *(const uint32 *)src_n);
+	}
+
+	/* skip lines in dst */
+	Colour *dst = (Colour *)bp->dst + bp->top * bp->pitch + bp->left;
+	assert(VideoDriver::GetInstance()->GetAnimBuffer() != nullptr);
+	uint8 *anim = VideoDriver::GetInstance()->GetAnimBuffer() + ((uint32 *)bp->dst - (uint32 *)_screen.dst_ptr) + bp->top * bp->pitch + bp->left;
+
+	/* store so we don't have to access it via bp everytime (compiler assumes pointer aliasing) */
+	const byte *remap = bp->remap;
+
+	for (int y = 0; y < bp->height; y++) {
+		/* next dst line begins here */
+		Colour *dst_ln = dst + bp->pitch;
+		uint8 *anim_ln = anim + bp->pitch;
+
+		/* next src line begins here */
+		const Colour *src_px_ln = (const Colour *)((const byte *)src_px + *(const uint32 *)src_px);
+		src_px++;
+
+		/* next src_n line begins here */
+		const uint16 *src_n_ln = (const uint16 *)((const byte *)src_n + *(const uint32 *)src_n);
+		src_n += 2;
+
+		/* we will end this line when we reach this point */
+		Colour *dst_end = dst + bp->skip_left;
+
+		/* number of pixels with the same alpha channel class */
+		uint n;
+
+		while (dst < dst_end) {
+			n = *src_n++;
+
+			if (src_px->a == 0) {
+				dst += n;
+				src_px++;
+				src_n++;
+
+				if (dst > dst_end) anim += dst - dst_end;
+			} else {
+				if (dst + n > dst_end) {
+					uint d = dst_end - dst;
+					src_px += d;
+					src_n += d;
+
+					dst = dst_end - bp->skip_left;
+					dst_end = dst + bp->width;
+
+					n = std::min<uint>(n - d, (uint)bp->width);
+					goto draw;
+				}
+				dst += n;
+				src_px += n;
+				src_n += n;
+			}
+		}
+
+		dst -= bp->skip_left;
+		dst_end -= bp->skip_left;
+
+		dst_end += bp->width;
+
+		while (dst < dst_end) {
+			n = std::min<uint>(*src_n++, (uint)(dst_end - dst));
+
+			if (src_px->a == 0) {
+				anim += n;
+				dst += n;
+				src_px++;
+				src_n++;
+				continue;
+			}
+
+			draw:;
+
+			switch (mode) {
+				case BM_COLOUR_REMAP:
+				case BM_CRASH_REMAP:
+					if (src_px->a == 255) {
+						do {
+							uint8 m = GB(*src_n, 0, 8);
+							/* In case the m-channel is zero, only apply the crash remap by darkening the RGB colour. */
+							if (m == 0) {
+								*dst = mode == BM_CRASH_REMAP ? this->MakeDark(*src_px) : *src_px;
+								*anim = 0;
+							} else {
+								uint r = remap[m];
+								if (r != 0) {
+									*dst = src_px->data;
+									*anim = r;
+								}
+							}
+							anim++;
+							dst++;
+							src_px++;
+							src_n++;
+						} while (--n != 0);
+					} else {
+						do {
+							uint8 m = GB(*src_n, 0, 8);
+							Colour b = this->RealizeBlendedColour(*anim, *dst);
+							if (m == 0) {
+								Colour c = mode == BM_CRASH_REMAP ? this->MakeDark(*src_px) : *src_px;
+								*dst = this->ComposeColourRGBANoCheck(c.r, c.g, c.b, src_px->a, b);
+								*anim = 0;
+							} else {
+								uint r = remap[m];
+								if (r != 0) {
+									*dst = this->ComposeColourPANoCheck(this->LookupColourInPalette(r), src_px->a, b);
+									*anim = 0; // Animation colours don't work with alpha-blending.
+								}
+							}
+							anim++;
+							dst++;
+							src_px++;
+							src_n++;
+						} while (--n != 0);
+					}
+					break;
+
+				case BM_BLACK_REMAP:
+					do {
+						*anim++ = 0;
+						*dst++ = _black_colour;
+						src_px++;
+						src_n++;
+					} while (--n != 0);
+					break;
+
+				case BM_TRANSPARENT:
+					/* TODO -- We make an assumption here that the remap in fact is transparency, not some colour.
+					 *  This is never a problem with the code we produce, but newgrfs can make it fail... or at least:
+					 *  we produce a result the newgrf maker didn't expect ;) */
+
+					/* Make the current colour a bit more black, so it looks like this image is transparent */
+					src_n += n;
+					if (src_px->a == 255) {
+						src_px += n;
+						do {
+							/* If the anim buffer contains a color value, the image composition will
+							 * only look at the RGB brightness value. As such, we can simply darken the
+							 * RGB value to darken the anim color. */
+							Colour b = *anim != 0 ? Colour(this->GetColourBrightness(*dst), 0, 0) : *dst;
+							*dst = this->MakeTransparent(b, 3, 4);
+							anim++;
+							dst++;
+						} while (--n != 0);
+					} else {
+						do {
+							Colour b = this->RealizeBlendedColour(*anim, *dst);
+							*dst = this->MakeTransparent(b, (256 * 4 - src_px->a), 256 * 4);
+							*anim = 0; // Animation colours don't work with alpha-blending.
+							anim++;
+							dst++;
+							src_px++;
+						} while (--n != 0);
+					}
+					break;
+
+				default:
+					if (src_px->a == 255) {
+						do {
+							*anim++ = GB(*src_n, 0, 8);
+							*dst++ = src_px->data;
+							src_px++;
+							src_n++;
+						} while (--n != 0);
+						break;
+					} else {
+						do {
+							uint8 m = GB(*src_n, 0, 8);
+							Colour b = this->RealizeBlendedColour(*anim, *dst);
+
+							if (m == 0) {
+								*dst = this->ComposeColourRGBANoCheck(src_px->r, src_px->g, src_px->b, src_px->a, b);
+								*anim = 0;
+							} else {
+								*dst = this->ComposeColourPANoCheck(this->LookupColourInPalette(m), src_px->a, b);
+								*anim = m;
+							}
+
+							anim++;
+							dst++;
+							src_px++;
+							src_n++;
+						} while (--n != 0);
+					}
+			}
+		}
+
+		dst = dst_ln;
+		anim = anim_ln;
+		src_px = src_px_ln;
+		src_n  = src_n_ln;
+	}
+}
+
+/**
+ * Draws a sprite to a (screen) buffer. Calls adequate templated function.
+ *
+ * @param bp further blitting parameters
+ * @param mode blitter mode
+ * @param zoom zoom level at which we are drawing
+ */
+void Blitter_40bppAnim::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
+{
+	assert(_screen.dst_ptr != nullptr);
+
+	if (_screen_disable_anim || VideoDriver::GetInstance()->GetAnimBuffer() == nullptr) {
+		/* This means our output is not to the screen, so we can't be doing any animation stuff, so use our parent Draw() */
+		Blitter_32bppOptimized::Draw(bp, mode, zoom);
+		return;
+	}
+
+	switch (mode) {
+		default: NOT_REACHED();
+		case BM_NORMAL:       Draw<BM_NORMAL>      (bp, zoom); return;
+		case BM_COLOUR_REMAP: Draw<BM_COLOUR_REMAP>(bp, zoom); return;
+		case BM_TRANSPARENT:  Draw<BM_TRANSPARENT> (bp, zoom); return;
+		case BM_CRASH_REMAP:  Draw<BM_CRASH_REMAP> (bp, zoom); return;
+		case BM_BLACK_REMAP:  Draw<BM_BLACK_REMAP> (bp, zoom); return;
+	}
+}
+
+void Blitter_40bppAnim::DrawColourMappingRect(void *dst, int width, int height, PaletteID pal)
+{
+	if (_screen_disable_anim) {
+		/* This means our output is not to the screen, so we can't be doing any animation stuff, so use our parent DrawColourMappingRect() */
+		Blitter_32bppOptimized::DrawColourMappingRect(dst, width, height, pal);
+		return;
+	}
+
+	Colour *udst = (Colour *)dst;
+	uint8 *anim = VideoDriver::GetInstance()->GetAnimBuffer() + ((uint32 *)dst - (uint32 *)_screen.dst_ptr);
+
+	if (pal == PALETTE_TO_TRANSPARENT) {
+		/* If the anim buffer contains a color value, the image composition will
+		 * only look at the RGB brightness value. As such, we can simply darken the
+		 * RGB value to darken the anim color. */
+		do {
+			for (int i = 0; i != width; i++) {
+				Colour b = *anim != 0 ? Colour(this->GetColourBrightness(*udst), 0, 0) : *udst;
+				*udst = MakeTransparent(b, 154);
+				udst++;
+				anim++;
+			}
+			udst = udst - width + _screen.pitch;
+			anim = anim - width + _screen.pitch;
+		} while (--height);
+	} else if (pal == PALETTE_NEWSPAPER) {
+		const uint8 *remap = GetNonSprite(pal, ST_RECOLOUR) + 1;
+		do {
+			for (int i = 0; i != width; i++) {
+				if (*anim == 0) *udst = MakeGrey(*udst);
+				*anim = remap[*anim];
+				udst++;
+				anim++;
+			}
+			udst = udst - width + _screen.pitch;
+			anim = anim - width + _screen.pitch;
+		} while (--height);
+	} else {
+		const uint8 *remap = GetNonSprite(pal, ST_RECOLOUR) + 1;
+		do {
+			for (int i = 0; i != width; i++) {
+				*anim = remap[*anim];
+				anim++;
+			}
+			anim = anim - width + _screen.pitch;
+		} while (--height);
+	}
+}
+
+Sprite *Blitter_40bppAnim::Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator)
+{
+	return this->EncodeInternal<false>(sprite, allocator);
+}
+
+
+void Blitter_40bppAnim::CopyFromBuffer(void *video, const void *src, int width, int height)
+{
+	assert(!_screen_disable_anim);
+	assert(video >= _screen.dst_ptr && video <= (uint32 *)_screen.dst_ptr + _screen.width + _screen.height * _screen.pitch);
+	uint32 *dst = (uint32 *)video;
+	const uint32 *usrc = (const uint32 *)src;
+
+	uint8 *anim_buf = VideoDriver::GetInstance()->GetAnimBuffer();
+	if (anim_buf == nullptr) return;
+	uint8 *anim_line = ((uint32 *)video - (uint32 *)_screen.dst_ptr) + anim_buf;
+
+	for (; height > 0; height--) {
+		memcpy(dst, usrc, width * sizeof(uint32));
+		usrc += width;
+		dst += _screen.pitch;
+		/* Copy back the anim-buffer */
+		memcpy(anim_line, usrc, width * sizeof(uint8));
+		usrc = (const uint32 *)((const uint8 *)usrc + width);
+		anim_line += _screen.pitch;
+	}
+}
+
+void Blitter_40bppAnim::CopyToBuffer(const void *video, void *dst, int width, int height)
+{
+	assert(!_screen_disable_anim);
+	assert(video >= _screen.dst_ptr && video <= (uint32 *)_screen.dst_ptr + _screen.width + _screen.height * _screen.pitch);
+	uint32 *udst = (uint32 *)dst;
+	const uint32 *src = (const uint32 *)video;
+
+	uint8 *anim_buf = VideoDriver::GetInstance()->GetAnimBuffer();
+	if (anim_buf == nullptr) return;
+	const uint8 *anim_line = ((const uint32 *)video - (uint32 *)_screen.dst_ptr) + anim_buf;
+
+	for (; height > 0; height--) {
+		memcpy(udst, src, width * sizeof(uint32));
+		src += _screen.pitch;
+		udst += width;
+		/* Copy the anim-buffer */
+		memcpy(udst, anim_line, width * sizeof(uint8));
+		udst = (uint32 *)((uint8 *)udst + width);
+		anim_line += _screen.pitch;
+	}
+}
+
+void Blitter_40bppAnim::CopyImageToBuffer(const void *video, void *dst, int width, int height, int dst_pitch)
+{
+	uint8 *anim_buf = VideoDriver::GetInstance()->GetAnimBuffer();
+	if (anim_buf == nullptr) {
+		Blitter_32bppOptimized::CopyImageToBuffer(video, dst, width, height, dst_pitch);
+		return;
+	}
+
+	uint32 *udst = (uint32 *)dst;
+	const uint32 *src = (const uint32 *)video;
+	const uint8 *anim_line = ((const uint32 *)video - (uint32 *)_screen.dst_ptr) + anim_buf;
+
+	for (; height > 0; height--) {
+		for (int x = 0; x < width; x++) {
+			udst[x] = this->RealizeBlendedColour(anim_line[x], src[x]).data;
+		}
+		src += _screen.pitch;
+		anim_line += _screen.pitch;
+		udst += dst_pitch;
+	}
+}
+
+void Blitter_40bppAnim::ScrollBuffer(void *video, int &left, int &top, int &width, int &height, int scroll_x, int scroll_y)
+{
+	assert(!_screen_disable_anim);
+	assert(video >= _screen.dst_ptr && video <= (uint32 *)_screen.dst_ptr + _screen.width + _screen.height * _screen.pitch);
+	uint8 *anim_buf = VideoDriver::GetInstance()->GetAnimBuffer();
+	uint8 *dst, *src;
+
+	/* We need to scroll the anim-buffer too */
+	if (scroll_y > 0) {
+		dst = anim_buf + left + (top + height - 1) * _screen.pitch;
+		src = dst - scroll_y * _screen.pitch;
+
+		/* Adjust left & width */
+		if (scroll_x >= 0) {
+			dst += scroll_x;
+		} else {
+			src -= scroll_x;
+		}
+
+		uint tw = width + (scroll_x >= 0 ? -scroll_x : scroll_x);
+		uint th = height - scroll_y;
+		for (; th > 0; th--) {
+			memcpy(dst, src, tw * sizeof(uint8));
+			src -= _screen.pitch;
+			dst -= _screen.pitch;
+		}
+	} else {
+		/* Calculate pointers */
+		dst = anim_buf + left + top * _screen.pitch;
+		src = dst - scroll_y * _screen.pitch;
+
+		/* Adjust left & width */
+		if (scroll_x >= 0) {
+			dst += scroll_x;
+		} else {
+			src -= scroll_x;
+		}
+
+		/* the y-displacement may be 0 therefore we have to use memmove,
+		 * because source and destination may overlap */
+		uint tw = width + (scroll_x >= 0 ? -scroll_x : scroll_x);
+		uint th = height + scroll_y;
+		for (; th > 0; th--) {
+			memmove(dst, src, tw * sizeof(uint8));
+			src += _screen.pitch;
+			dst += _screen.pitch;
+		}
+	}
+
+	Blitter_32bppBase::ScrollBuffer(video, left, top, width, height, scroll_x, scroll_y);
+}
+
+int Blitter_40bppAnim::BufferSize(int width, int height)
+{
+	return width * height * (sizeof(uint32) + sizeof(uint8));
+}
+
+Blitter::PaletteAnimation Blitter_40bppAnim::UsePaletteAnimation()
+{
+	return Blitter::PALETTE_ANIMATION_VIDEO_BACKEND;
+}
+
+bool Blitter_40bppAnim::NeedsAnimationBuffer()
+{
+	return true;
+}
diff --git a/src/blitter/40bpp_anim.hpp b/src/blitter/40bpp_anim.hpp
new file mode 100644
index 000000000..8d7e6ce32
--- /dev/null
+++ b/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 */
diff --git a/src/blitter/CMakeLists.txt b/src/blitter/CMakeLists.txt
index 0aff38141..ddcc9a008 100644
--- a/src/blitter/CMakeLists.txt
+++ b/src/blitter/CMakeLists.txt
@@ -32,6 +32,13 @@ add_files(
     CONDITION NOT OPTION_DEDICATED AND SSE_FOUND
 )
 
+add_files(
+    40bpp_anim.cpp
+    40bpp_anim.hpp
+    CONDITION NOT OPTION_DEDICATED AND OPENGL_FOUND
+)
+
+
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
     set_compile_flags(
         32bpp_anim_sse2.cpp