WINTERMUTE: Add transparentSurface internally for now, to allow alpha-blended blits.

2 files changed, 446 insertions, 0 deletions

diff --git a/engines/wintermute/graphics/transparentSurface.cpp b/engines/wintermute/graphics/transparentSurface.cpp
new file mode 100644
index 0000000000..c8ac9f1a2c
--- /dev/null
+++ b/engines/wintermute/graphics/transparentSurface.cpp
@@ -0,0 +1,322 @@
+/* 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "common/algorithm.h"
+#include "common/endian.h"
+#include "common/util.h"
+#include "common/rect.h"
+#include "common/textconsole.h"
+#include "graphics/primitives.h"
+#include "engines/wintermute/graphics/transparentSurface.h"
+
+namespace WinterMute {
+
+TransparentSurface::TransparentSurface() : Surface() {}
+
+TransparentSurface::TransparentSurface(const Surface &surf, bool copyData) : Surface() {
+	if (copyData) {
+		copyFrom(surf);
+	} else {
+		w = surf.w;
+		h = surf.h;
+		pitch = surf.pitch;
+		format = surf.format;
+		pixels = surf.pixels;
+	}
+}
+
+Common::Rect TransparentSurface::blit(Graphics::Surface &target, int posX, int posY, int flipping, Common::Rect *pPartRect, uint color, int width, int height) {
+	int ca = (color >> 24) & 0xff;
+
+	Common::Rect retSize;
+	retSize.top = 0;
+	retSize.left = 0;
+	retSize.setWidth(0);
+	retSize.setHeight(0);
+	// Check if we need to draw anything at all
+	if (ca == 0)
+		return retSize;
+
+	int cr = (color >> 16) & 0xff;
+	int cg = (color >> 8) & 0xff;
+	int cb = (color >> 0) & 0xff;
+
+	// Compensate for transparency. Since we're coming
+	// down to 255 alpha, we just compensate for the colors here
+	if (ca != 255) {
+		cr = cr * ca >> 8;
+		cg = cg * ca >> 8;
+		cb = cb * ca >> 8;
+	}
+
+	// Create an encapsulating surface for the data
+	TransparentSurface srcImage(*this, false);
+	// TODO: Is the data really in the screen format?
+	if (format.bytesPerPixel != 4) {
+		error("TransparentSurface can only blit 32 bpp images");
+	}
+
+	if (pPartRect) {
+		srcImage.pixels = &((char *)pixels)[pPartRect->top * srcImage.pitch + pPartRect->left * 4];
+		srcImage.w = pPartRect->width();
+		srcImage.h = pPartRect->height();
+
+		debug(6, "Blit(%d, %d, %d, [%d, %d, %d, %d], %08x, %d, %d)", posX, posY, flipping,
+		      pPartRect->left,  pPartRect->top, pPartRect->width(), pPartRect->height(), color, width, height);
+	} else {
+
+		debug(6, "Blit(%d, %d, %d, [%d, %d, %d, %d], %08x, %d, %d)", posX, posY, flipping, 0, 0,
+		      srcImage.w, srcImage.h, color, width, height);
+	}
+
+	if (width == -1)
+		width = srcImage.w;
+	if (height == -1)
+		height = srcImage.h;
+
+#ifdef SCALING_TESTING
+	// Hardcode scaling to 66% to test scaling
+	width = width * 2 / 3;
+	height = height * 2 / 3;
+#endif
+
+	Graphics::Surface *img;
+	Graphics::Surface *imgScaled = NULL;
+	byte *savedPixels = NULL;
+	if ((width != srcImage.w) || (height != srcImage.h)) {
+		// Scale the image
+		img = imgScaled = srcImage.scale(width, height);
+		savedPixels = (byte *)img->pixels;
+	} else {
+		img = &srcImage;
+	}
+
+	// Handle off-screen clipping
+	if (posY < 0) {
+		img->h = MAX(0, (int)img->h - -posY);
+		img->pixels = (byte *)img->pixels + img->pitch * -posY;
+		posY = 0;
+	}
+
+	if (posX < 0) {
+		img->w = MAX(0, (int)img->w - -posX);
+		img->pixels = (byte *)img->pixels + (-posX * 4);
+		posX = 0;
+	}
+
+	img->w = CLIP((int)img->w, 0, (int)MAX((int)target.w - posX, 0));
+	img->h = CLIP((int)img->h, 0, (int)MAX((int)target.h - posY, 0));
+
+	if ((img->w > 0) && (img->h > 0)) {
+		int xp = 0, yp = 0;
+
+		int inStep = 4;
+		int inoStep = img->pitch;
+		if (flipping & TransparentSurface::FLIP_V) {
+			inStep = -inStep;
+			xp = img->w - 1;
+		}
+
+		if (flipping & TransparentSurface::FLIP_H) {
+			inoStep = -inoStep;
+			yp = img->h - 1;
+		}
+
+		byte *ino = (byte *)img->getBasePtr(xp, yp);
+		byte *outo = (byte *)target.getBasePtr(posX, posY);
+		byte *in, *out;
+
+		int bShift = img->format.bShift;
+		int gShift = img->format.gShift;
+		int rShift = img->format.rShift;
+		int aShift = img->format.aShift;
+
+		int bShiftTarget = target.format.bShift;
+		int gShiftTarget = target.format.gShift;
+		int rShiftTarget = target.format.rShift;
+		int aShiftTarget = target.format.aShift;
+
+		for (int i = 0; i < img->h; i++) {
+			out = outo;
+			in = ino;
+			for (int j = 0; j < img->w; j++) {
+				uint32 pix = *(uint32 *)in;
+				uint32 o_pix = *(uint32 *) out;
+				int b = (pix >> bShift) & 0xff;
+				int g = (pix >> gShift) & 0xff;
+				int r = (pix >> rShift) & 0xff;
+				int a = (pix >> aShift) & 0xff;
+				int o_b, o_g, o_r, o_a;
+				in += inStep;
+
+				if (ca != 255) {
+					a = a * ca >> 8;
+				}
+
+				switch (a) {
+				case 0: // Full transparency
+					out += 4;
+					break;
+				case 255: // Full opacity
+					if (cb != 255)
+						o_b = (b * cb) >> 8;
+					else
+						o_b = b;
+
+					if (cg != 255)
+						o_g = (g * cg) >> 8;
+					else
+						o_g = g;
+
+					if (cr != 255)
+						o_r = (r * cr) >> 8;
+					else
+						o_r = r;
+					o_a = a;
+					*(uint32 *)out = target.format.ARGBToColor(o_a, o_r, o_g, o_b);
+					out += 4;
+					break;
+
+				default: // alpha blending
+					o_a = 255;
+					o_b = (o_pix >> bShiftTarget) & 0xff;
+					o_g = (o_pix >> gShiftTarget) & 0xff;
+					o_r = (o_pix >> rShiftTarget) & 0xff;
+					if (cb == 0)
+						o_b = 0;
+					else if (cb != 255)
+						o_b += ((b - o_b) * a * cb) >> 16;
+					else
+						o_b += ((b - o_b) * a) >> 8;
+					if (cg == 0)
+						o_g = 0;
+					else if (cg != 255)
+						o_g += ((g - o_g) * a * cg) >> 16;
+					else
+						o_g += ((g - o_g) * a) >> 8;
+					if (cr == 0)
+						o_r = 0;
+					else if (cr != 255)
+						o_r += ((r - o_r) * a * cr) >> 16;
+					else
+						o_r += ((r - o_r) * a) >> 8;
+					*(uint32 *)out = target.format.ARGBToColor(o_a, o_r, o_g, o_b);
+					out += 4;
+				}
+			}
+			outo += target.pitch;
+			ino += inoStep;
+		}
+	}
+
+	if (imgScaled) {
+		imgScaled->pixels = savedPixels;
+		imgScaled->free();
+		delete imgScaled;
+	}
+
+	retSize.setWidth(img->w);
+	retSize.setHeight(img->h);
+	return retSize;
+}
+
+/**
+ * Scales a passed surface, creating a new surface with the result
+ * @param srcImage      Source image to scale
+ * @param scaleFactor   Scale amount. Must be between 0 and 1.0 (but not zero)
+ * @remarks Caller is responsible for freeing the returned surface
+ */
+TransparentSurface *TransparentSurface::scale(int xSize, int ySize) const {
+	TransparentSurface *s = new TransparentSurface();
+	s->create(xSize, ySize, this->format);
+
+	int *horizUsage = scaleLine(xSize, this->w);
+	int *vertUsage = scaleLine(ySize, this->h);
+
+	// Loop to create scaled version
+	for (int yp = 0; yp < ySize; ++yp) {
+		const byte *srcP = (const byte *)this->getBasePtr(0, vertUsage[yp]);
+		byte *destP = (byte *)s->getBasePtr(0, yp);
+
+		for (int xp = 0; xp < xSize; ++xp) {
+			const byte *tempSrcP = srcP + (horizUsage[xp] * this->format.bytesPerPixel);
+			for (int byteCtr = 0; byteCtr < this->format.bytesPerPixel; ++byteCtr) {
+				*destP++ = *tempSrcP++;
+			}
+		}
+	}
+
+	// Delete arrays and return surface
+	delete[] horizUsage;
+	delete[] vertUsage;
+	return s;
+}
+
+/**
+ * Writes a color key to the alpha channel of the surface
+ * @param rKey  the red component of the color key
+ * @param gKey  the green component of the color key
+ * @param bKey  the blue component of the color key
+ * @param overwriteAlpha if true, all other alpha will be set fully opaque
+ */
+void TransparentSurface::applyColorKey(uint8 rKey, uint8 gKey, uint8 bKey, bool overwriteAlpha) {
+	for (int i = 0; i < h; i++) {
+		for (int j = 0; j < w; j++) {
+			uint32 pix = ((uint32 *)pixels)[i * w + j];
+			uint8 r, g, b, a;
+			format.colorToARGB(pix, a, r, g, b);
+			if (r == rKey && g == gKey && b == bKey) {
+				a = 0;
+				((uint32 *)pixels)[i * w + j] = format.ARGBToColor(a, r, g, b);
+			} else if (overwriteAlpha) {
+				a = 255;
+				((uint32 *)pixels)[i * w + j] = format.ARGBToColor(a, r, g, b);
+			}
+		}
+	}
+}
+
+/**
+ * Returns an array indicating which pixels of a source image horizontally or vertically get
+ * included in a scaled image
+ */
+int *TransparentSurface::scaleLine(int size, int srcSize) {
+	int scale = 100 * size / srcSize;
+	assert(scale > 0);
+	int *v = new int[size];
+	Common::fill(v, &v[size], 0);
+
+	int distCtr = 0;
+	int *destP = v;
+	for (int distIndex = 0; distIndex < srcSize; ++distIndex) {
+		distCtr += scale;
+		while (distCtr >= 100) {
+			assert(destP < &v[size]);
+			*destP++ = distIndex;
+			distCtr -= 100;
+		}
+	}
+
+	return v;
+}
+
+
+} // End of namespace Graphics
diff --git a/engines/wintermute/graphics/transparentSurface.h b/engines/wintermute/graphics/transparentSurface.h
new file mode 100644
index 0000000000..e271bf2488
--- /dev/null
+++ b/engines/wintermute/graphics/transparentSurface.h
@@ -0,0 +1,124 @@
+/* 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef GRAPHICS_TRANSPARENTSURFACE_H
+#define GRAPHICS_TRANSPARENTSURFACE_H
+
+#include "graphics/surface.h"
+
+/*
+ * This code is based on Broken Sword 2.5 engine
+ *
+ * Copyright (c) Malte Thiesen, Daniel Queteschiner and Michael Elsdoerfer
+ *
+ * Licensed under GNU GPL v2
+ *
+ */
+
+// TODO: Find a better solution for this.
+#define BS_RGB(R,G,B)       (0xFF000000 | ((R) << 16) | ((G) << 8) | (B))
+#define BS_ARGB(A,R,G,B)    (((A) << 24) | ((R) << 16) | ((G) << 8) | (B))
+
+namespace WinterMute {
+
+/**
+ * A transparent graphics surface, which implements alpha blitting.
+ */
+struct TransparentSurface : public Graphics::Surface {
+	TransparentSurface();
+	TransparentSurface(const Graphics::Surface &surf, bool copyData = false);
+
+	void setColorKey(char r, char g, char b);
+	void disableColorKey();
+
+	// Enums
+	/**
+	 @brief The possible flipping parameters for the blit methode.
+	 */
+	enum FLIP_FLAGS {
+	    /// The image will not be flipped.
+	    FLIP_NONE = 0,
+	    /// The image will be flipped at the horizontal axis.
+	    FLIP_H = 1,
+	    /// The image will be flipped at the vertical axis.
+	    FLIP_V = 2,
+	    /// The image will be flipped at the horizontal and vertical axis.
+	    FLIP_HV = FLIP_H | FLIP_V,
+	    /// The image will be flipped at the horizontal and vertical axis.
+	    FLIP_VH = FLIP_H | FLIP_V
+	};
+
+	/**
+	 @brief renders the surface to another surface
+	 @param pDest a pointer to the target image. In most cases this is the framebuffer.
+	 @param PosX the position on the X-axis in the target image in pixels where the image is supposed to be rendered.<br>
+	 The default value is 0.
+	 @param PosY the position on the Y-axis in the target image in pixels where the image is supposed to be rendered.<br>
+	 The default value is 0.
+	 @param Flipping how the the image should be flipped.<br>
+	 The default value is BS_Image::FLIP_NONE (no flipping)
+	 @param pSrcPartRect Pointer on Common::Rect which specifies the section to be rendered. If the whole image has to be rendered the Pointer is NULL.<br>
+	 This referes to the unflipped and unscaled image.<br>
+	 The default value is NULL.
+	 @param Color an ARGB color value, which determines the parameters for the color modulation und alpha blending.<br>
+	 The alpha component of the color determines the alpha blending parameter (0 = no covering, 255 = full covering).<br>
+	 The color components determines the color for color modulation.<br>
+	 The default value is BS_ARGB(255, 255, 255, 255) (full covering, no color modulation).
+	 The macros BS_RGB and BS_ARGB can be used for the creation of the color value.
+	 @param Width the output width of the screen section.
+	 The images will be scaled if the output width of the screen section differs from the image section.<br>
+	 The value -1 determines that the image should not be scaled.<br>
+	 The default value is -1.
+	 @param Width the output height of the screen section.
+	 The images will be scaled if the output width of the screen section differs from the image section.<br>
+	 The value -1 determines that the image should not be scaled.<br>
+	 The default value is -1.
+	 @return returns false if the rendering failed.
+	 */
+
+	Common::Rect blit(Graphics::Surface &target, int posX = 0, int posY = 0,
+	                  int flipping = FLIP_NONE,
+	                  Common::Rect *pPartRect = NULL,
+	                  uint color = BS_ARGB(255, 255, 255, 255),
+	                  int width = -1, int height = -1);
+	void applyColorKey(uint8 r, uint8 g, uint8 b, bool overwriteAlpha = false);
+	TransparentSurface *scale(int xSize, int ySize) const;
+private:
+	static int *scaleLine(int size, int srcSize);
+};
+
+/**
+ * A deleter for Surface objects which can be used with SharedPtr.
+ *
+ * This deleter assures Surface::free is called on deletion.
+ */
+/*struct SharedPtrTransparentSurfaceDeleter {
+    void operator()(TransparentSurface *ptr) {
+        ptr->free();
+        delete ptr;
+    }
+};*/
+
+
+} // End of namespace Graphics
+
+
+#endif