imagedata.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

 * @param destOrder the destination byte ordering: one of MSB_FIRST or LSB_FIRST;
 *        ignored if destDepth is not 16 or 32
 * @param destX the top-left x-coord of the destination blit region
 * @param destY the top-left y-coord of the destination blit region
 * @param destWidth the width of the destination blit region
 * @param destHeight the height of the destination blit region
 * @param destRedMask the destination red channel mask
 * @param destGreenMask the destination green channel mask
 * @param destBlueMask the destination blue channel mask
 * @param flipX if true the resulting image is flipped along the vertical axis
 * @param flipY if true the resulting image is flipped along the horizontal axis
 */
static void blit(int op,
	byte[] srcData, int srcDepth, int srcStride, int srcOrder,
	int srcX, int srcY, int srcWidth, int srcHeight,
	int srcRedMask, int srcGreenMask, int srcBlueMask,
	int alphaMode, byte[] alphaData, int alphaStride, int alphaX, int alphaY,
	byte[] destData, int destDepth, int destStride, int destOrder,
	int destX, int destY, int destWidth, int destHeight,
	int destRedMask, int destGreenMask, int destBlueMask,
	boolean flipX, boolean flipY) {
	if ((destWidth <= 0) || (destHeight <= 0) || (alphaMode == ALPHA_TRANSPARENT)) return;

	// these should be supplied as params later
	final int srcAlphaMask = 0, destAlphaMask = 0;

	/*** Prepare scaling data ***/
	final int dwm1 = destWidth - 1;
	final int sfxi = (dwm1 != 0) ? (int)((((long)srcWidth << 16) - 1) / dwm1) : 0;
	final int dhm1 = destHeight - 1;
	final int sfyi = (dhm1 != 0) ? (int)((((long)srcHeight << 16) - 1) / dhm1) : 0;

	/*** Prepare source-related data ***/
	final int sbpp, stype;
	switch (srcDepth) {
		case 8:
			sbpp = 1;
			stype = TYPE_GENERIC_8;
			break;
		case 16:
			sbpp = 2;
			stype = (srcOrder == MSB_FIRST) ? TYPE_GENERIC_16_MSB : TYPE_GENERIC_16_LSB;
			break;
		case 24:
			sbpp = 3;
			stype = TYPE_GENERIC_24;
			break;
		case 32:
			sbpp = 4;
			stype = (srcOrder == MSB_FIRST) ? TYPE_GENERIC_32_MSB : TYPE_GENERIC_32_LSB;
			break;
		default:
			//throw new IllegalArgumentException("Invalid source type");
			return;
	}			
	int spr = srcY * srcStride + srcX * sbpp;

	/*** Prepare destination-related data ***/
	final int dbpp, dtype;
	switch (destDepth) {
		case 8:
			dbpp = 1;
			dtype = TYPE_GENERIC_8;
			break;
		case 16:
			dbpp = 2;
			dtype = (destOrder == MSB_FIRST) ? TYPE_GENERIC_16_MSB : TYPE_GENERIC_16_LSB;
			break;
		case 24:
			dbpp = 3;
			dtype = TYPE_GENERIC_24;
			break;
		case 32:
			dbpp = 4;
			dtype = (destOrder == MSB_FIRST) ? TYPE_GENERIC_32_MSB : TYPE_GENERIC_32_LSB;
			break;
		default:
			//throw new IllegalArgumentException("Invalid destination type");
			return;
	}			
	int dpr = ((flipY) ? destY + dhm1 : destY) * destStride + ((flipX) ? destX + dwm1 : destX) * dbpp;
	final int dprxi = (flipX) ? -dbpp : dbpp;
	final int dpryi = (flipY) ? -destStride : destStride;

	/*** Prepare special processing data ***/
	int apr;
	if ((op & BLIT_ALPHA) != 0) {
		switch (alphaMode) {
			case ALPHA_MASK_UNPACKED:
			case ALPHA_CHANNEL_SEPARATE:
				if (alphaData == null) alphaMode = 0x10000;
				apr = alphaY * alphaStride + alphaX;
				break;
			case ALPHA_MASK_PACKED:
				if (alphaData == null) alphaMode = 0x10000;
				alphaStride <<= 3;
				apr = alphaY * alphaStride + alphaX;
				break;
			case ALPHA_MASK_INDEX:
				//throw new IllegalArgumentException("Invalid alpha type");
				return;
			case ALPHA_MASK_RGB:
				if (alphaData == null) alphaMode = 0x10000;
				apr = 0;
				break;
			default:
				alphaMode = (alphaMode << 16) / 255; // prescale
			case ALPHA_CHANNEL_SOURCE:
				apr = 0;
				break;
		}
	} else {
		alphaMode = 0x10000;
		apr = 0;
	}

	/*** Blit ***/
	int dp = dpr;
	int sp = spr;
	if ((alphaMode == 0x10000) && (stype == dtype) &&
		(srcRedMask == destRedMask) && (srcGreenMask == destGreenMask) &&
		(srcBlueMask == destBlueMask) && (srcAlphaMask == destAlphaMask)) {
		/*** Fast blit (straight copy) ***/
		switch (sbpp) {
			case 1:
				for (int dy = destHeight, sfy = sfyi; dy > 0; --dy, sp = spr += (sfy >>> 16) * srcStride, sfy = (sfy & 0xffff) + sfyi, dp = dpr += dpryi) {
					for (int dx = destWidth, sfx = sfxi; dx > 0; --dx, dp += dprxi, sfx = (sfx & 0xffff) + sfxi) {
						destData[dp] = srcData[sp];
						sp += (sfx >>> 16);
					}
				}
				break;					
			case 2:
				for (int dy = destHeight, sfy = sfyi; dy > 0; --dy, sp = spr += (sfy >>> 16) * srcStride, sfy = (sfy & 0xffff) + sfyi, dp = dpr += dpryi) {
					for (int dx = destWidth, sfx = sfxi; dx > 0; --dx, dp += dprxi, sfx = (sfx & 0xffff) + sfxi) {
						destData[dp] = srcData[sp];
						destData[dp + 1] = srcData[sp + 1];
						sp += (sfx >>> 16) * 2;
					}
				}
				break;
			case 3:
				for (int dy = destHeight, sfy = sfyi; dy > 0; --dy, sp = spr += (sfy >>> 16) * srcStride, sfy = (sfy & 0xffff) + sfyi, dp = dpr += dpryi) {
					for (int dx = destWidth, sfx = sfxi; dx > 0; --dx, dp += dprxi, sfx = (sfx & 0xffff) + sfxi) {
						destData[dp] = srcData[sp];
						destData[dp + 1] = srcData[sp + 1];
						destData[dp + 2] = srcData[sp + 2];
						sp += (sfx >>> 16) * 3;
					}
				}
				break;
			case 4:
				for (int dy = destHeight, sfy = sfyi; dy > 0; --dy, sp = spr += (sfy >>> 16) * srcStride, sfy = (sfy & 0xffff) + sfyi, dp = dpr += dpryi) {
					for (int dx = destWidth, sfx = sfxi; dx > 0; --dx, dp += dprxi, sfx = (sfx & 0xffff) + sfxi) {
						destData[dp] = srcData[sp];
						destData[dp + 1] = srcData[sp + 1];
						destData[dp + 2] = srcData[sp + 2];
						destData[dp + 3] = srcData[sp + 3];
						sp += (sfx >>> 16) * 4;
					}
				}
				break;
		}
		return;
	}
	/*** Comprehensive blit (apply transformations) ***/
	final int srcRedShift = getChannelShift(srcRedMask);
	final byte[] srcReds = ANY_TO_EIGHT[getChannelWidth(srcRedMask, srcRedShift)];
	final int srcGreenShift = getChannelShift(srcGreenMask);
	final byte[] srcGreens = ANY_TO_EIGHT[getChannelWidth(srcGreenMask, srcGreenShift)];
	final int srcBlueShift = getChannelShift(srcBlueMask);
	final byte[] srcBlues = ANY_TO_EIGHT[getChannelWidth(srcBlueMask, srcBlueShift)];
	final int srcAlphaShift = getChannelShift(srcAlphaMask);
	final byte[] srcAlphas = ANY_TO_EIGHT[getChannelWidth(srcAlphaMask, srcAlphaShift)];

	final int destRedShift = getChannelShift(destRedMask);
	final int destRedWidth = getChannelWidth(destRedMask, destRedShift);
	final byte[] destReds = ANY_TO_EIGHT[destRedWidth];
	final int destRedPreShift = 8 - destRedWidth;
	final int destGreenShift = getChannelShift(destGreenMask);
	final int destGreenWidth = getChannelWidth(destGreenMask, destGreenShift);
	final byte[] destGreens = ANY_TO_EIGHT[destGreenWidth];
	final int destGreenPreShift = 8 - destGreenWidth;
	final int destBlueShift = getChannelShift(destBlueMask);
	final int destBlueWidth = getChannelWidth(destBlueMask, destBlueShift);
	final byte[] destBlues = ANY_TO_EIGHT[destBlueWidth];
	final int destBluePreShift = 8 - destBlueWidth;
	final int destAlphaShift = getChannelShift(destAlphaMask);
	final int destAlphaWidth = getChannelWidth(destAlphaMask, destAlphaShift);
	final byte[] destAlphas = ANY_TO_EIGHT[destAlphaWidth];
	final int destAlphaPreShift = 8 - destAlphaWidth;

	int ap = apr, alpha = alphaMode;
	int r = 0, g = 0, b = 0, a = 0;
	int rq = 0, gq = 0, bq = 0, aq = 0;
	for (int dy = destHeight, sfy = sfyi; dy > 0; --dy,
			sp = spr += (sfy >>> 16) * srcStride,
			ap = apr += (sfy >>> 16) * alphaStride,
			sfy = (sfy & 0xffff) + sfyi,
			dp = dpr += dpryi) {
		for (int dx = destWidth, sfx = sfxi; dx > 0; --dx,
				dp += dprxi,
				sfx = (sfx & 0xffff) + sfxi) {
			/*** READ NEXT PIXEL ***/
			switch (stype) {
				case TYPE_GENERIC_8: {
					final int data = srcData[sp] & 0xff;
					sp += (sfx >>> 16);
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
				case TYPE_GENERIC_16_MSB: {
					final int data = ((srcData[sp] & 0xff) << 8) | (srcData[sp + 1] & 0xff);
					sp += (sfx >>> 16) * 2;
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
				case TYPE_GENERIC_16_LSB: {
					final int data = ((srcData[sp + 1] & 0xff) << 8) | (srcData[sp] & 0xff);
					sp += (sfx >>> 16) * 2;
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
				case TYPE_GENERIC_24: {
					final int data = (( ((srcData[sp] & 0xff) << 8) |
						(srcData[sp + 1] & 0xff)) << 8) |
						(srcData[sp + 2] & 0xff);
					sp += (sfx >>> 16) * 3;
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
				case TYPE_GENERIC_32_MSB: {
					final int data = (( (( ((srcData[sp] & 0xff) << 8) |
						(srcData[sp + 1] & 0xff)) << 8) |
						(srcData[sp + 2] & 0xff)) << 8) |
						(srcData[sp + 3] & 0xff);
					sp += (sfx >>> 16) * 4;
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
				case TYPE_GENERIC_32_LSB: {
					final int data = (( (( ((srcData[sp + 3] & 0xff) << 8) |
						(srcData[sp + 2] & 0xff)) << 8) |
						(srcData[sp + 1] & 0xff)) << 8) |
						(srcData[sp] & 0xff);
					sp += (sfx >>> 16) * 4;
					r = srcReds[(data & srcRedMask) >>> srcRedShift] & 0xff;
					g = srcGreens[(data & srcGreenMask) >>> srcGreenShift] & 0xff;
					b = srcBlues[(data & srcBlueMask) >>> srcBlueShift] & 0xff;
					a = srcAlphas[(data & srcAlphaMask) >>> srcAlphaShift] & 0xff;
				} break;
			}

			/*** DO SPECIAL PROCESSING IF REQUIRED ***/
			switch (alphaMode) {
				case ALPHA_CHANNEL_SEPARATE:
					alpha = ((alphaData[ap] & 0xff) << 16) / 255;
					ap += (sfx >> 16);
					break;
				case ALPHA_CHANNEL_SOURCE:
					alpha = (a << 16) / 255;
					break;
				case ALPHA_MASK_UNPACKED:
					alpha = (alphaData[ap] != 0) ? 0x10000 : 0;
					ap += (sfx >> 16);
					break;						
				case ALPHA_MASK_PACKED:
					alpha = (alphaData[ap >> 3] << ((ap & 7) + 9)) & 0x10000;
					ap += (sfx >> 16);
					break;
				case ALPHA_MASK_RGB:
					alpha = 0x10000;
					for (int i = 0; i < alphaData.length; i += 3) {
						if ((r == alphaData[i]) && (g == alphaData[i + 1]) && (b == alphaData[i + 2])) {
							alpha = 0x0000;
							break;
						}
					}
					break;
			}
			if (alpha != 0x10000) {
				if (alpha == 0x0000) continue;
				switch (dtype) {
					case TYPE_GENERIC_8: {
						final int data = destData[dp] & 0xff;
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
					case TYPE_GENERIC_16_MSB: {
						final int data = ((destData[dp] & 0xff) << 8) | (destData[dp + 1] & 0xff);
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
					case TYPE_GENERIC_16_LSB: {
						final int data = ((destData[dp + 1] & 0xff) << 8) | (destData[dp] & 0xff);
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
					case TYPE_GENERIC_24: {
						final int data = (( ((destData[dp] & 0xff) << 8) |
							(destData[dp + 1] & 0xff)) << 8) |
							(destData[dp + 2] & 0xff);
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
					case TYPE_GENERIC_32_MSB: {
						final int data = (( (( ((destData[dp] & 0xff) << 8) |
							(destData[dp + 1] & 0xff)) << 8) |
							(destData[dp + 2] & 0xff)) << 8) |
							(destData[dp + 3] & 0xff);
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
					case TYPE_GENERIC_32_LSB: {
						final int data = (( (( ((destData[dp + 3] & 0xff) << 8) |
							(destData[dp + 2] & 0xff)) << 8) |
							(destData[dp + 1] & 0xff)) << 8) |
							(destData[dp] & 0xff);
						rq = destReds[(data & destRedMask) >>> destRedShift] & 0xff;
						gq = destGreens[(data & destGreenMask) >>> destGreenShift] & 0xff;
						bq = destBlues[(data & destBlueMask) >>> destBlueShift] & 0xff;
						aq = destAlphas[(data & destAlphaMask) >>> destAlphaShift] & 0xff;
					} break;
				}
				// Perform alpha blending
				a = aq + ((a - aq) * alpha >> 16);
				r = rq + ((r - rq) * alpha >> 16);
				g = gq + ((g - gq) * alpha >> 16);
				b = bq + ((b - bq) * alpha >> 16);
			}

			/*** WRITE NEXT PIXEL ***/
			final int data = 
				(r >>> destRedPreShift << destRedShift) |
				(g >>> destGreenPreShift << destGreenShift) |
				(b >>> destBluePreShift << destBlueShift) |
				(a >>> destAlphaPreShift << destAlphaShift);
			switch (dtype) {
				case TYPE_GENERIC_8: {
					destData[dp] = (byte) data;
				} break;
				case TYPE_GENERIC_16_MSB: {
					destData[dp] = (byte) (data >>> 8);
					destData[dp + 1] = (byte) (data & 0xff);
				} break;
				case TYPE_GENERIC_16_LSB: {
					destData[dp] = (byte) (data & 0xff);
					destData[dp + 1] = (byte) (data >>> 8);
				} break;
				case TYPE_GENERIC_24: {
					destData[dp] = (byte) (data >>> 16);
					destData[dp + 1] = (byte) (data >>> 8);
					destData[dp + 2] = (byte) (data & 0xff);
				} break;
				case TYPE_GENERIC_32_MSB: {
					destData[dp] = (byte) (data >>> 24);
					destData[dp + 1] = (byte) (data >>> 16);
					destData[dp + 2] = (byte) (data >>> 8);
					destData[dp + 3] = (byte) (data & 0xff);
				} break;
				case TYPE_GENERIC_32_LSB: {
					destData[dp] = (byte) (data & 0xff);
					destData[dp + 1] = (byte) (data >>> 8);
					destData[dp + 2] = (byte) (data >>> 16);
					destData[dp + 3] = (byte) (data >>> 24);
				} break;
			}
		}
	}			
}

/**
 * Blits an index palette image into an index palette image.
 * <p>
 * Note: The source and destination red, green, and blue
 * arrays may be null if no alpha blending or dither is to be
 * performed.
 * </p>
 * 
 * @param op the blitter operation: a combination of BLIT_xxx flags
 *        (see BLIT_xxx constants)
 * @param srcData the source byte array containing image data
 * @param srcDepth the source depth: one of 1, 2, 4, 8
 * @param srcStride the source number of bytes per line
 * @param srcOrder the source byte ordering: one of MSB_FIRST or LSB_FIRST;
 *        ignored if srcDepth is not 1
 * @param srcX the top-left x-coord of the source blit region
 * @param srcY the top-left y-coord of the source blit region
 * @param srcWidth the width of the source blit region
 * @param srcHeight the height of the source blit region
 * @param srcReds the source palette red component intensities
 * @param srcGreens the source palette green component intensities
 * @param srcBlues the source palette blue component intensities
 * @param alphaMode the alpha blending or mask mode, may be
 *        an integer 0-255 for global alpha; ignored if BLIT_ALPHA
 *        not specified in the blitter operations
 *        (see ALPHA_MODE_xxx constants)
 * @param alphaData the alpha blending or mask data, varies depending
 *        on the value of alphaMode and sometimes ignored
 * @param alphaStride the alpha data number of bytes per line
 * @param alphaX the top-left x-coord of the alpha blit region
 * @param alphaY the top-left y-coord of the alpha blit region
 * @param destData the destination byte array containing image data
 * @param destDepth the destination depth: one of 1, 2, 4, 8
 * @param destStride the destination number of bytes per line
 * @param destOrder the destination by