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diff --git a/plugins/FreeImage/src/FreeImageToolkit/Display.cpp b/plugins/FreeImage/src/FreeImageToolkit/Display.cpp
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+// ==========================================================
+// Display routines
+//
+// Design and implementation by
+// - Hervé Drolon (drolon@infonie.fr)
+//
+// This file is part of FreeImage 3
+//
+// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
+// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
+// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
+// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
+// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
+// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
+// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
+// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
+// THIS DISCLAIMER.
+//
+// Use at your own risk!
+// ==========================================================
+
+#include "FreeImage.h"
+#include "Utilities.h"
+
+
+/**
+@brief Composite a foreground image against a background color or a background image.
+
+The equation for computing a composited sample value is:<br>
+output = alpha * foreground + (1-alpha) * background<br>
+where alpha and the input and output sample values are expressed as fractions in the range 0 to 1. 
+For colour images, the computation is done separately for R, G, and B samples.
+
+@param fg Foreground image
+@param useFileBkg If TRUE and a file background is present, use it as the background color
+@param appBkColor If not equal to NULL, and useFileBkg is FALSE, use this color as the background color
+@param bg If not equal to NULL and useFileBkg is FALSE and appBkColor is NULL, use this as the background image
+@return Returns the composite image if successful, returns NULL otherwise
+@see FreeImage_IsTransparent, FreeImage_HasBackgroundColor
+*/
+FIBITMAP * DLL_CALLCONV
+FreeImage_Composite(FIBITMAP *fg, BOOL useFileBkg, RGBQUAD *appBkColor, FIBITMAP *bg) {
+	if (!FreeImage_HasPixels(fg)) return NULL;
+
+	int width  = FreeImage_GetWidth(fg);
+	int height = FreeImage_GetHeight(fg);
+	int bpp    = FreeImage_GetBPP(fg);
+
+	if ((bpp != 8) && (bpp != 32))
+		return NULL;
+
+	if(bg) {
+		int bg_width  = FreeImage_GetWidth(bg);
+		int bg_height = FreeImage_GetHeight(bg);
+		int bg_bpp    = FreeImage_GetBPP(bg);
+		if ((bg_width != width) || (bg_height != height) || (bg_bpp != 24))
+			return NULL;
+	}
+
+	int bytespp = (bpp == 8) ? 1 : 4;
+
+	
+	int x, y, c;
+	BYTE alpha = 0, not_alpha;
+	BYTE index;
+	RGBQUAD fgc;	// foreground color
+	RGBQUAD bkc;	// background color
+
+	memset(&fgc, 0, sizeof(RGBQUAD));
+	memset(&bkc, 0, sizeof(RGBQUAD));
+
+	// allocate the composite image
+	FIBITMAP *composite = FreeImage_Allocate(width, height, 24, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
+	if (!composite) return NULL;
+
+	// get the palette
+	RGBQUAD *pal = FreeImage_GetPalette(fg);
+
+	// retrieve the alpha table from the foreground image
+	BOOL bIsTransparent = FreeImage_IsTransparent(fg);
+	BYTE *trns = FreeImage_GetTransparencyTable(fg);
+
+	// retrieve the background color from the foreground image
+	BOOL bHasBkColor = FALSE;
+
+	if(useFileBkg && FreeImage_HasBackgroundColor(fg)) {
+		FreeImage_GetBackgroundColor(fg, &bkc);
+		bHasBkColor = TRUE;
+	} else {
+		// no file background color
+		// use application background color ?
+		if(appBkColor) {
+			memcpy(&bkc, appBkColor, sizeof(RGBQUAD));
+			bHasBkColor = TRUE;
+		}
+		// use background image ?
+		else if(bg) {
+			bHasBkColor = FALSE;
+		}
+	}
+
+	for(y = 0; y < height; y++) {
+		// foreground
+		BYTE *fg_bits = FreeImage_GetScanLine(fg, y);
+		// background
+		BYTE *bg_bits = FreeImage_GetScanLine(bg, y);
+		// composite image
+		BYTE *cp_bits = FreeImage_GetScanLine(composite, y);
+
+		for(x = 0; x < width; x++) {
+
+			// foreground color + alpha
+
+			if(bpp == 8) {
+				// get the foreground color
+				index = fg_bits[0];
+				memcpy(&fgc, &pal[index], sizeof(RGBQUAD));
+				// get the alpha
+				if(bIsTransparent) {
+					alpha = trns[index];
+				} else {
+					alpha = 255;
+				}
+			}
+			else if(bpp == 32) {
+				// get the foreground color
+				fgc.rgbBlue  = fg_bits[FI_RGBA_BLUE];
+				fgc.rgbGreen = fg_bits[FI_RGBA_GREEN];
+				fgc.rgbRed   = fg_bits[FI_RGBA_RED];
+				// get the alpha
+				alpha = fg_bits[FI_RGBA_ALPHA];
+			}
+
+			// background color
+
+			if (!bHasBkColor) {
+				if(bg) {
+					// get the background color from the background image
+					bkc.rgbBlue  = bg_bits[FI_RGBA_BLUE];
+					bkc.rgbGreen = bg_bits[FI_RGBA_GREEN];
+					bkc.rgbRed   = bg_bits[FI_RGBA_RED];
+				}
+				else {
+					// use a checkerboard pattern
+					c = (((y & 0x8) == 0) ^ ((x & 0x8) == 0)) * 192;
+					c = c ? c : 255;
+					bkc.rgbBlue  = (BYTE)c;
+					bkc.rgbGreen = (BYTE)c;
+					bkc.rgbRed   = (BYTE)c;
+				}
+			}
+
+			// composition
+
+			if(alpha == 0) {
+				// output = background
+				cp_bits[FI_RGBA_BLUE] = bkc.rgbBlue;
+				cp_bits[FI_RGBA_GREEN] = bkc.rgbGreen;
+				cp_bits[FI_RGBA_RED] = bkc.rgbRed;
+			}
+			else if(alpha == 255) {
+				// output = foreground
+				cp_bits[FI_RGBA_BLUE] = fgc.rgbBlue;
+				cp_bits[FI_RGBA_GREEN] = fgc.rgbGreen;
+				cp_bits[FI_RGBA_RED] = fgc.rgbRed;
+			}
+			else {
+				// output = alpha * foreground + (1-alpha) * background
+				not_alpha = (BYTE)~alpha;
+				cp_bits[FI_RGBA_BLUE] = (BYTE)((alpha * (WORD)fgc.rgbBlue  + not_alpha * (WORD)bkc.rgbBlue) >> 8);
+				cp_bits[FI_RGBA_GREEN] = (BYTE)((alpha * (WORD)fgc.rgbGreen + not_alpha * (WORD)bkc.rgbGreen) >> 8);
+				cp_bits[FI_RGBA_RED] = (BYTE)((alpha * (WORD)fgc.rgbRed   + not_alpha * (WORD)bkc.rgbRed) >> 8);
+			}
+
+			fg_bits += bytespp;
+			bg_bits += 3;
+			cp_bits += 3;
+		}
+	}
+
+	// copy metadata from src to dst
+	FreeImage_CloneMetadata(composite, fg);
+	
+	return composite;	
+}
+
+/**
+Pre-multiplies a 32-bit image's red-, green- and blue channels with it's alpha channel 
+for to be used with e.g. the Windows GDI function AlphaBlend(). 
+The transformation changes the red-, green- and blue channels according to the following equation:  
+channel(x, y) = channel(x, y) * alpha_channel(x, y) / 255  
+@param dib Input/Output dib to be premultiplied
+@return Returns TRUE on success, FALSE otherwise (e.g. when the bitdepth of the source dib cannot be handled). 
+*/
+BOOL DLL_CALLCONV 
+FreeImage_PreMultiplyWithAlpha(FIBITMAP *dib) {
+	if (!FreeImage_HasPixels(dib)) return FALSE;
+	
+	if ((FreeImage_GetBPP(dib) != 32) || (FreeImage_GetImageType(dib) != FIT_BITMAP)) {
+		return FALSE;
+	}
+
+	int width = FreeImage_GetWidth(dib);
+	int height = FreeImage_GetHeight(dib);
+
+	for(int y = 0; y < height; y++) {
+		BYTE *bits = FreeImage_GetScanLine(dib, y);
+		for (int x = 0; x < width; x++, bits += 4) {
+			const BYTE alpha = bits[FI_RGBA_ALPHA];
+			// slightly faster: care for two special cases
+			if(alpha == 0x00) {
+				// special case for alpha == 0x00
+				// color * 0x00 / 0xFF = 0x00
+				bits[FI_RGBA_BLUE] = 0x00;
+				bits[FI_RGBA_GREEN] = 0x00;
+				bits[FI_RGBA_RED] = 0x00;
+			} else if(alpha == 0xFF) {
+				// nothing to do for alpha == 0xFF
+				// color * 0xFF / 0xFF = color
+				continue;
+			} else {
+				bits[FI_RGBA_BLUE] = (BYTE)( (alpha * (WORD)bits[FI_RGBA_BLUE] + 127) / 255 );
+				bits[FI_RGBA_GREEN] = (BYTE)( (alpha * (WORD)bits[FI_RGBA_GREEN] + 127) / 255 );
+				bits[FI_RGBA_RED] = (BYTE)( (alpha * (WORD)bits[FI_RGBA_RED] + 127) / 255 );
+			}
+		}
+	}
+	return TRUE;
+}
+