/* ScummVM - Scumm Interpreter * Copyright (C) 2001 Ludvig Strigeus * Copyright (C) 2001-2003 The ScummVM project * * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * $Header$ * */ #include "stdafx.h" #include "common/scummsys.h" #include "common/scaler.h" // TODO: get rid of the colorMask etc. variables and instead use templates. // This should give a respectable boost, since variable access (i.e. memory reads) // in the innermost loops of our operations would work with constant data instead. // That should help the inliner; reduce memory access; thus improve cache efficeny // etc. The drawback will be that each scaler will exist twice, once for 555 and // once for 555, resulting in the object file being twice as big (but thanks to // templates, no source code would be duplicated. static uint32 colorMask = 0xF7DEF7DE; static uint32 lowPixelMask = 0x08210821; static uint32 qcolorMask = 0xE79CE79C; static uint32 qlowpixelMask = 0x18631863; static uint32 redblueMask = 0xF81F; static uint32 redMask = 0xF800; static uint32 greenMask = 0x07E0; static uint32 blueMask = 0x001F; static const uint16 dotmatrix_565[16] = { 0x01E0, 0x0007, 0x3800, 0x0000, 0x39E7, 0x0000, 0x39E7, 0x0000, 0x3800, 0x0000, 0x01E0, 0x0007, 0x39E7, 0x0000, 0x39E7, 0x0000 }; static const uint16 dotmatrix_555[16] = { 0x00E0, 0x0007, 0x1C00, 0x0000, 0x1CE7, 0x0000, 0x1CE7, 0x0000, 0x1C00, 0x0000, 0x00E0, 0x0007, 0x1CE7, 0x0000, 0x1CE7, 0x0000 }; static const uint16 *dotmatrix; int Init_2xSaI(uint32 BitFormat) { if (BitFormat == 565) { colorMask = 0xF7DEF7DE; lowPixelMask = 0x08210821; qcolorMask = 0xE79CE79C; qlowpixelMask = 0x18631863; redblueMask = 0xF81F; redMask = 0xF800; greenMask = 0x07E0; blueMask = 0x001F; dotmatrix = dotmatrix_565; } else if (BitFormat == 555) { colorMask = 0x7BDE7BDE; lowPixelMask = 0x04210421; qcolorMask = 0x739C739C; qlowpixelMask = 0x0C630C63; redblueMask = 0x7C1F; redMask = 0x7C00; greenMask = 0x03E0; blueMask = 0x001F; dotmatrix = dotmatrix_555; } else { return 0; } return 1; } static inline int GetResult(uint32 A, uint32 B, uint32 C, uint32 D) { const bool ac = (A==C); const bool bc = (B==C); const int x1 = ac; const int y1 = (bc & !ac); const bool ad = (A==D); const bool bd = (B==D); const int x2 = ad; const int y2 = (bd & !ad); const int x = x1+x2; const int y = y1+y2; static const int rmap[3][3] = { {0, 0, -1}, {0, 0, -1}, {1, 1, 0} }; return rmap[y][x]; } static inline uint32 INTERPOLATE(uint32 A, uint32 B) { if (A != B) { return (((A & colorMask) >> 1) + ((B & colorMask) >> 1) + (A & B & lowPixelMask)); } else return A; } static inline uint32 Q_INTERPOLATE(uint32 A, uint32 B, uint32 C, uint32 D) { register uint32 x = ((A & qcolorMask) >> 2) + ((B & qcolorMask) >> 2) + ((C & qcolorMask) >> 2) + ((D & qcolorMask) >> 2); register uint32 y = ((A & qlowpixelMask) + (B & qlowpixelMask) + (C & qlowpixelMask) + (D & qlowpixelMask)) >> 2; y &= qlowpixelMask; return x + y; } void Super2xSaI(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { const uint16 *bP; uint16 *dP; const uint32 nextlineSrc = srcPitch >> 1; while (height--) { bP = (const uint16 *)srcPtr; dP = (uint16 *)dstPtr; for (int i = 0; i < width; ++i) { uint32 color4, color5, color6; uint32 color1, color2, color3; uint32 colorA0, colorA1, colorA2, colorA3; uint32 colorB0, colorB1, colorB2, colorB3; uint32 colorS1, colorS2; uint32 product1a, product1b, product2a, product2b; //--------------------------------------- B1 B2 // 4 5 6 S2 // 1 2 3 S1 // A1 A2 colorB0 = *(bP - nextlineSrc - 1); colorB1 = *(bP - nextlineSrc); colorB2 = *(bP - nextlineSrc + 1); colorB3 = *(bP - nextlineSrc + 2); color4 = *(bP - 1); color5 = *(bP); color6 = *(bP + 1); colorS2 = *(bP + 2); color1 = *(bP + nextlineSrc - 1); color2 = *(bP + nextlineSrc); color3 = *(bP + nextlineSrc + 1); colorS1 = *(bP + nextlineSrc + 2); colorA0 = *(bP + 2 * nextlineSrc - 1); colorA1 = *(bP + 2 * nextlineSrc); colorA2 = *(bP + 2 * nextlineSrc + 1); colorA3 = *(bP + 2 * nextlineSrc + 2); //-------------------------------------- if (color2 == color6 && color5 != color3) { product2b = product1b = color2; } else if (color5 == color3 && color2 != color6) { product2b = product1b = color5; } else if (color5 == color3 && color2 == color6) { register int r = 0; r += GetResult(color6, color5, color1, colorA1); r += GetResult(color6, color5, color4, colorB1); r += GetResult(color6, color5, colorA2, colorS1); r += GetResult(color6, color5, colorB2, colorS2); if (r > 0) product2b = product1b = color6; else if (r < 0) product2b = product1b = color5; else { product2b = product1b = INTERPOLATE(color5, color6); } } else { if (color6 == color3 && color3 == colorA1 && color2 != colorA2 && color3 != colorA0) product2b = Q_INTERPOLATE(color3, color3, color3, color2); else if (color5 == color2 && color2 == colorA2 && colorA1 != color3 && color2 != colorA3) product2b = Q_INTERPOLATE(color2, color2, color2, color3); else product2b = INTERPOLATE(color2, color3); if (color6 == color3 && color6 == colorB1 && color5 != colorB2 && color6 != colorB0) product1b = Q_INTERPOLATE(color6, color6, color6, color5); else if (color5 == color2 && color5 == colorB2 && colorB1 != color6 && color5 != colorB3) product1b = Q_INTERPOLATE(color6, color5, color5, color5); else product1b = INTERPOLATE(color5, color6); } if (color5 == color3 && color2 != color6 && color4 == color5 && color5 != colorA2) product2a = INTERPOLATE(color2, color5); else if (color5 == color1 && color6 == color5 && color4 != color2 && color5 != colorA0) product2a = INTERPOLATE(color2, color5); else product2a = color2; if (color2 == color6 && color5 != color3 && color1 == color2 && color2 != colorB2) product1a = INTERPOLATE(color2, color5); else if (color4 == color2 && color3 == color2 && color1 != color5 && color2 != colorB0) product1a = INTERPOLATE(color2, color5); else product1a = color5; *(dP + 0) = (uint16) product1a; *(dP + 1) = (uint16) product1b; *(dP + dstPitch/2 + 0) = (uint16) product2a; *(dP + dstPitch/2 + 1) = (uint16) product2b; bP += 1; dP += 2; } srcPtr += srcPitch; dstPtr += dstPitch * 2; } } void SuperEagle(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { const uint16 *bP; uint16 *dP; const uint32 nextlineSrc = srcPitch >> 1; while (height--) { bP = (const uint16 *)srcPtr; dP = (uint16 *)dstPtr; for (int i = 0; i < width; ++i) { uint32 color4, color5, color6; uint32 color1, color2, color3; uint32 colorA1, colorA2, colorB1, colorB2, colorS1, colorS2; uint32 product1a, product1b, product2a, product2b; colorB1 = *(bP - nextlineSrc); colorB2 = *(bP - nextlineSrc + 1); color4 = *(bP - 1); color5 = *(bP); color6 = *(bP + 1); colorS2 = *(bP + 2); color1 = *(bP + nextlineSrc - 1); color2 = *(bP + nextlineSrc); color3 = *(bP + nextlineSrc + 1); colorS1 = *(bP + nextlineSrc + 2); colorA1 = *(bP + 2 * nextlineSrc); colorA2 = *(bP + 2 * nextlineSrc + 1); // -------------------------------------- if (color5 != color3) { if (color2 == color6) { product1b = product2a = color2; if ((color1 == color2) || (color6 == colorB2)) { product1a = INTERPOLATE(color2, color5); product1a = INTERPOLATE(color2, product1a); } else { product1a = INTERPOLATE(color5, color6); } if ((color6 == colorS2) || (color2 == colorA1)) { product2b = INTERPOLATE(color2, color3); product2b = INTERPOLATE(color2, product2b); } else { product2b = INTERPOLATE(color2, color3); } } else { product2b = product1a = INTERPOLATE(color2, color6); product2b = Q_INTERPOLATE(color3, color3, color3, product2b); product1a = Q_INTERPOLATE(color5, color5, color5, product1a); product2a = product1b = INTERPOLATE(color5, color3); product2a = Q_INTERPOLATE(color2, color2, color2, product2a); product1b = Q_INTERPOLATE(color6, color6, color6, product1b); } } else //if (color5 == color3) { if (color2 != color6) { product2b = product1a = color5; if ((colorB1 == color5) || (color3 == colorS1)) { product1b = INTERPOLATE(color5, color6); product1b = INTERPOLATE(color5, product1b); } else { product1b = INTERPOLATE(color5, color6); } if ((color3 == colorA2) || (color4 == color5)) { product2a = INTERPOLATE(color5, color2); product2a = INTERPOLATE(color5, product2a); } else { product2a = INTERPOLATE(color2, color3); } } else //if (color2 != color6) { register int r = 0; r += GetResult(color6, color5, color1, colorA1); r += GetResult(color6, color5, color4, colorB1); r += GetResult(color6, color5, colorA2, colorS1); r += GetResult(color6, color5, colorB2, colorS2); if (r > 0) { product1b = product2a = color2; product1a = product2b = INTERPOLATE(color5, color6); } else if (r < 0) { product2b = product1a = color5; product1b = product2a = INTERPOLATE(color5, color6); } else { product2b = product1a = color5; product1b = product2a = color2; } } } *(dP + 0) = (uint16) product1a; *(dP + 1) = (uint16) product1b; *(dP + dstPitch/2 + 0) = (uint16) product2a; *(dP + dstPitch/2 + 1) = (uint16) product2b; bP += 1; dP += 2; } srcPtr += srcPitch; dstPtr += dstPitch * 2; } } void _2xSaI(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { const uint16 *bP; uint16 *dP; const uint32 nextlineSrc = srcPitch >> 1; while (height--) { bP = (const uint16 *)srcPtr; dP = (uint16 *)dstPtr; for (int i = 0; i < width; ++i) { register uint32 colorA, colorB; uint32 colorC, colorD, colorE, colorF, colorG, colorH, colorI, colorJ, colorK, colorL, colorM, colorN, colorO, colorP; uint32 product, product1, product2; //--------------------------------------- // Map of the pixels: I|E F|J // G|A B|K // H|C D|L // M|N O|P colorI = *(bP - nextlineSrc - 1); colorE = *(bP - nextlineSrc); colorF = *(bP - nextlineSrc + 1); colorJ = *(bP - nextlineSrc + 2); colorG = *(bP - 1); colorA = *(bP); colorB = *(bP + 1); colorK = *(bP + 2); colorH = *(bP + nextlineSrc - 1); colorC = *(bP + nextlineSrc); colorD = *(bP + nextlineSrc + 1); colorL = *(bP + nextlineSrc + 2); colorM = *(bP + 2 * nextlineSrc - 1); colorN = *(bP + 2 * nextlineSrc); colorO = *(bP + 2 * nextlineSrc + 1); colorP = *(bP + 2 * nextlineSrc + 2); if ((colorA == colorD) && (colorB != colorC)) { if (((colorA == colorE) && (colorB == colorL)) || ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ))) { product = colorA; } else { product = INTERPOLATE(colorA, colorB); } if (((colorA == colorG) && (colorC == colorO)) || ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM))) { product1 = colorA; } else { product1 = INTERPOLATE(colorA, colorC); } product2 = colorA; } else if ((colorB == colorC) && (colorA != colorD)) { if (((colorB == colorF) && (colorA == colorH)) || ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI))) { product = colorB; } else { product = INTERPOLATE(colorA, colorB); } if (((colorC == colorH) && (colorA == colorF)) || ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI))) { product1 = colorC; } else { product1 = INTERPOLATE(colorA, colorC); } product2 = colorB; } else if ((colorA == colorD) && (colorB == colorC)) { if (colorA == colorB) { product = colorA; product1 = colorA; product2 = colorA; } else { register int r = 0; product1 = INTERPOLATE(colorA, colorC); product = INTERPOLATE(colorA, colorB); r += GetResult(colorA, colorB, colorG, colorE); r -= GetResult(colorB, colorA, colorK, colorF); r -= GetResult(colorB, colorA, colorH, colorN); r += GetResult(colorA, colorB, colorL, colorO); if (r > 0) product2 = colorA; else if (r < 0) product2 = colorB; else { product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD); } } } else { product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD); if ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ)) { product = colorA; } else if ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI)) { product = colorB; } else { product = INTERPOLATE(colorA, colorB); } if ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM)) { product1 = colorA; } else if ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI)) { product1 = colorC; } else { product1 = INTERPOLATE(colorA, colorC); } } *(dP + 0) = (uint16) colorA; *(dP + 1) = (uint16) product; *(dP + dstPitch/2 + 0) = (uint16) product1; *(dP + dstPitch/2 + 1) = (uint16) product2; bP += 1; dP += 2; } srcPtr += srcPitch; dstPtr += dstPitch * 2; } } void AdvMame2x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { unsigned int nextlineSrc = srcPitch / sizeof(uint16); const uint16 *p = (const uint16 *)srcPtr; unsigned int nextlineDst = dstPitch / sizeof(uint16); uint16 *q = (uint16 *)dstPtr; uint16 A, B, C; uint16 D, E, F; uint16 G, H, I; while (height--) { B = *(p - 1 - nextlineSrc); E = *(p - 1); H = *(p - 1 + nextlineSrc); C = *(p - nextlineSrc); F = *(p); I = *(p + nextlineSrc); for (int i = 0; i < width; ++i) { p++; A = B; B = C; C = *(p - nextlineSrc); D = E; E = F; F = *(p); G = H; H = I; I = *(p + nextlineSrc); *(q) = D == B && B != F && D != H ? D : E; *(q + 1) = B == F && B != D && F != H ? F : E; *(q + nextlineDst) = D == H && D != B && H != F ? D : E; *(q + nextlineDst + 1) = H == F && D != H && B != F ? F : E; q += 2; } p += nextlineSrc - width; q += (nextlineDst - width) << 1; } } void AdvMame3x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { unsigned int nextlineSrc = srcPitch / sizeof(uint16); const uint16 *p = (const uint16 *)srcPtr; unsigned int nextlineDst = dstPitch / sizeof(uint16); uint16 *q = (uint16 *)dstPtr; uint16 A, B, C; uint16 D, E, F; uint16 G, H, I; while (height--) { B = *(p - 1 - nextlineSrc); E = *(p - 1); H = *(p - 1 + nextlineSrc); C = *(p - nextlineSrc); F = *(p); I = *(p + nextlineSrc); for (int i = 0; i < width; ++i) { p++; A = B; B = C; C = *(p - nextlineSrc); D = E; E = F; F = *(p); G = H; H = I; I = *(p + nextlineSrc); *(q) = D == B && B != F && D != H ? D : E; *(q + 1) = E; *(q + 2) = B == F && B != D && F != H ? F : E; *(q + nextlineDst) = E; *(q + nextlineDst + 1) = E; *(q + nextlineDst + 2) = E; *(q + 2 * nextlineDst) = D == H && D != B && H != F ? D : E; *(q + 2 * nextlineDst + 1) = E; *(q + 2 * nextlineDst + 2) = H == F && D != H && B != F ? F : E; q += 3; } p += nextlineSrc - width; q += (nextlineDst - width) * 3; } } void Normal1x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { while (height--) { memcpy(dstPtr, srcPtr, 2 * width); srcPtr += srcPitch; dstPtr += dstPitch; } } void Normal2x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { uint8 *r; while (height--) { r = dstPtr; for (int i = 0; i < width; ++i, r += 4) { uint16 color = *(((const uint16 *)srcPtr) + i); *(uint16 *)(r + 0) = color; *(uint16 *)(r + 2) = color; *(uint16 *)(r + 0 + dstPitch) = color; *(uint16 *)(r + 2 + dstPitch) = color; } srcPtr += srcPitch; dstPtr += dstPitch << 1; } } void Normal3x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { uint8 *r; uint32 dstPitch2 = dstPitch * 2; uint32 dstPitch3 = dstPitch * 3; while (height--) { r = dstPtr; for (int i = 0; i < width; ++i, r += 6) { uint16 color = *(((const uint16 *)srcPtr) + i); *(uint16 *)(r + 0) = color; *(uint16 *)(r + 2) = color; *(uint16 *)(r + 4) = color; *(uint16 *)(r + 0 + dstPitch) = color; *(uint16 *)(r + 2 + dstPitch) = color; *(uint16 *)(r + 4 + dstPitch) = color; *(uint16 *)(r + 0 + dstPitch2) = color; *(uint16 *)(r + 2 + dstPitch2) = color; *(uint16 *)(r + 4 + dstPitch2) = color; } srcPtr += srcPitch; dstPtr += dstPitch3; } } void TV2x(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { unsigned int nextlineSrc = srcPitch / sizeof(uint16); const uint16 *p = (const uint16 *)srcPtr; unsigned int nextlineDst = dstPitch / sizeof(uint16); uint16 *q = (uint16 *)dstPtr; while(height--) { for (int i = 0, j = 0; i < width; ++i, j += 2) { uint16 p1 = *(p + i); uint32 pi; pi = (((p1 & redblueMask) * 7) >> 3) & redblueMask; pi |= (((p1 & greenMask) * 7) >> 3) & greenMask; *(q + j) = p1; *(q + j + 1) = p1; *(q + j + nextlineDst) = (uint16)pi; *(q + j + nextlineDst + 1) = (uint16)pi; } p += nextlineSrc; q += nextlineDst << 1; } } static inline uint16 DOT_16(uint16 c, int j, int i) { return c - ((c >> 2) & *(dotmatrix + ((j & 3) << 2) + (i & 3))); } void DotMatrix(const uint8 *srcPtr, uint32 srcPitch, uint8 *dstPtr, uint32 dstPitch, int width, int height) { unsigned int nextlineSrc = srcPitch / sizeof(uint16); const uint16 *p = (const uint16 *)srcPtr; unsigned int nextlineDst = dstPitch / sizeof(uint16); uint16 *q = (uint16 *)dstPtr; for (int j = 0, jj = 0; j < height; ++j, jj += 2) { for (int i = 0, ii = 0; i < width; ++i, ii += 2) { uint16 c = *(p + i); *(q + ii) = DOT_16(c, jj, ii); *(q + ii + 1) = DOT_16(c, jj, ii + 1); *(q + ii + nextlineDst) = DOT_16(c, jj + 1, ii); *(q + ii + nextlineDst + 1) = DOT_16(c, jj + 1, ii + 1); } p += nextlineSrc; q += nextlineDst << 1; } } #define kVeryFastAndUglyAspectMode 0 // No interpolation at all, but super-fast #define kFastAndNiceAspectMode 1 // Quite good quality with good speed #define kSlowAndPerfectAspectMode 2 // Accurate but slow code #define ASPECT_MODE kFastAndNiceAspectMode #if ASPECT_MODE == kSlowAndPerfectAspectMode template static inline uint16 interpolate5(uint16 A, uint16 B) { uint16 r = (uint16)(((A & redMask) * scale + (B & redMask) * (5 - scale)) / 5); uint16 g = (uint16)(((A & greenMask) * scale + (B & greenMask) * (5 - scale)) / 5); uint16 b = (uint16)(((A & blueMask) * scale + (B & blueMask) * (5 - scale)) / 5); return (uint16)((r & redMask) | (g & greenMask) | (b & blueMask)); } template static inline void interpolate5Line(uint16 *dst, const uint16 *srcA, const uint16 *srcB, int width) { // Accurate but slightly slower code while (width--) { *dst++ = interpolate5(*srcA++, *srcB++); } } #endif #if ASPECT_MODE == kFastAndNiceAspectMode template static inline void interpolate5Line(uint16 *dst, const uint16 *srcA, const uint16 *srcB, int width) { // For efficiency reasons we blit two pixels at a time, so it is // important that makeRectStretchable() guarantees that the width is // even and that the rect starts on a well-aligned address. (Even // where unaligned memory access is allowed there may be a speed // penalty for it.) // These asserts are disabled for maximal speed; but I leave them in here in case // other people want to test if the memory alignment (to an address divisibl by 4) // are really effective. //assert(((int)dst & 3) == 0); //assert(((int)srcA & 3) == 0); //assert(((int)srcB & 3) == 0); //assert((width & 1) == 0); width /= 2; const uint32 *sA = (const uint32 *)srcA; const uint32 *sB = (const uint32 *)srcB; uint32 *d = (uint32 *)dst; if (scale == 1) { while (width--) { uint32 B = *sB++; *d++ = Q_INTERPOLATE(*sA++, B, B, B); } } else { while (width--) { *d++ = INTERPOLATE(*sA++, *sB++); } } } #endif void makeRectStretchable(int &x, int &y, int &w, int &h) { #if ASPECT_MODE != kVeryFastAndUglyAspectMode int m = real2Aspect(y) % 6; // Ensure that the rect will start on a line that won't have its // colours changed by the stretching function. if (m != 0 && m != 5) { y -= m; h += m; } #if ASPECT_MODE == kFastAndNiceAspectMode // Force x to be even, to ensure aligned memory access (this assumes // that each line starts at an even memory location, but that should // be the case on every target anyway). if (x & 1) { x--; w++; } // Finally force the width to be even, since we blit 2 pixels at a time. // While this means we may sometimes blit one column more than necessary, // this should actually be faster than having the check for the if (w & 1) w++; #endif #endif } /** * Stretch a 16bpp image vertically by factor 1.2. Used to correct the * aspect-ratio in games using 320x200 pixel graphics with non-qudratic * pixels. Applying this method effectively turns that into 320x240, which * provides the correct aspect-ratio on modern displays. * * The image would normally have occupied y coordinates origSrcY through * origSrcY + height - 1. * * However, we have already placed it at srcY - the aspect-corrected y * coordinate - to allow in-place stretching. * * Therefore, the source image now occupies Y coordinates srcY through * srcY + height - 1, and it should be stretched to Y coordinates srcY * through real2Aspect(srcY + height - 1). */ int stretch200To240(uint8 *buf, uint32 pitch, int width, int height, int srcX, int srcY, int origSrcY) { int maxDstY = real2Aspect(origSrcY + height - 1); int y; const uint8 *startSrcPtr = buf + srcX * 2 + (srcY - origSrcY) * pitch; uint8 *dstPtr = buf + srcX * 2 + maxDstY * pitch; for (y = maxDstY; y >= srcY; y--) { const uint8 *srcPtr = startSrcPtr + aspect2Real(y) * pitch; #if ASPECT_MODE == kVeryFastAndUglyAspectMode if (srcPtr == dstPtr) break; memcpy(dstPtr, srcPtr, width * 2); #else // Bilinear filter switch (y % 6) { case 0: case 5: if (srcPtr != dstPtr) memcpy(dstPtr, srcPtr, width * 2); break; case 1: case 4: interpolate5Line<1>((uint16 *)dstPtr, (const uint16 *)(srcPtr - pitch), (const uint16 *)srcPtr, width); break; case 2: case 3: interpolate5Line<2>((uint16 *)dstPtr, (const uint16 *)(srcPtr - pitch), (const uint16 *)srcPtr, width); break; } #endif dstPtr -= pitch; } return 1 + maxDstY - srcY; }