From bfc4902910b8a6be7eb1fad963928b805d6075fa Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Robert=20M=C3=BCller?= Date: Wed, 3 Jul 2024 23:27:56 +0200 Subject: [PATCH] Minor refactoring of `DilateImage` and related functions Add constants for BPP and alpha threshold during Dilate, as dilating only works for RGBA images and we only use a fixed alpha threshold. Move local variable declarations closer to their usages. Use `mem_copy` instead of for-loop. Use `nullptr` instead of `NULL`. --- src/engine/gfx/image_manipulation.cpp | 64 +++++++++++++-------------- 1 file changed, 30 insertions(+), 34 deletions(-) diff --git a/src/engine/gfx/image_manipulation.cpp b/src/engine/gfx/image_manipulation.cpp index c01bc3939..07f493856 100644 --- a/src/engine/gfx/image_manipulation.cpp +++ b/src/engine/gfx/image_manipulation.cpp @@ -2,38 +2,35 @@ #include #include -#define TW_DILATE_ALPHA_THRESHOLD 10 +static constexpr int DILATE_BPP = 4; // RGBA assumed +static constexpr uint8_t DILATE_ALPHA_THRESHOLD = 10; -static void Dilate(int w, int h, const uint8_t *pSrc, uint8_t *pDest, uint8_t AlphaThreshold = TW_DILATE_ALPHA_THRESHOLD) +static void Dilate(int w, int h, const uint8_t *pSrc, uint8_t *pDest) { - const int BPP = 4; // RGBA assumed - int ix, iy; const int aDirX[] = {0, -1, 1, 0}; const int aDirY[] = {-1, 0, 0, 1}; - int AlphaCompIndex = BPP - 1; - int m = 0; for(int y = 0; y < h; y++) { - for(int x = 0; x < w; x++, m += BPP) + for(int x = 0; x < w; x++, m += DILATE_BPP) { - for(int i = 0; i < BPP; ++i) + for(int i = 0; i < DILATE_BPP; ++i) pDest[m + i] = pSrc[m + i]; - if(pSrc[m + AlphaCompIndex] > AlphaThreshold) + if(pSrc[m + DILATE_BPP - 1] > DILATE_ALPHA_THRESHOLD) continue; int aSumOfOpaque[] = {0, 0, 0}; int Counter = 0; for(int c = 0; c < 4; c++) { - ix = clamp(x + aDirX[c], 0, w - 1); - iy = clamp(y + aDirY[c], 0, h - 1); - int k = iy * w * BPP + ix * BPP; - if(pSrc[k + AlphaCompIndex] > AlphaThreshold) + const int ClampedX = clamp(x + aDirX[c], 0, w - 1); + const int ClampedY = clamp(y + aDirY[c], 0, h - 1); + const int SrcIndex = ClampedY * w * DILATE_BPP + ClampedX * DILATE_BPP; + if(pSrc[SrcIndex + DILATE_BPP - 1] > DILATE_ALPHA_THRESHOLD) { - for(int p = 0; p < BPP - 1; ++p) - aSumOfOpaque[p] += pSrc[k + p]; + for(int p = 0; p < DILATE_BPP - 1; ++p) + aSumOfOpaque[p] += pSrc[SrcIndex + p]; ++Counter; break; } @@ -41,29 +38,28 @@ static void Dilate(int w, int h, const uint8_t *pSrc, uint8_t *pDest, uint8_t Al if(Counter > 0) { - for(int i = 0; i < BPP - 1; ++i) + for(int i = 0; i < DILATE_BPP - 1; ++i) { aSumOfOpaque[i] /= Counter; pDest[m + i] = (uint8_t)aSumOfOpaque[i]; } - pDest[m + AlphaCompIndex] = 255; + pDest[m + DILATE_BPP - 1] = 255; } } } } -static void CopyColorValues(int w, int h, int BPP, const uint8_t *pSrc, uint8_t *pDest) +static void CopyColorValues(int w, int h, const uint8_t *pSrc, uint8_t *pDest) { int m = 0; for(int y = 0; y < h; y++) { - for(int x = 0; x < w; x++, m += BPP) + for(int x = 0; x < w; x++, m += DILATE_BPP) { - for(int i = 0; i < BPP - 1; ++i) + if(pDest[m + DILATE_BPP - 1] == 0) { - if(pDest[m + 3] == 0) - pDest[m + i] = pSrc[m + i]; + mem_copy(&pDest[m], &pSrc[m], DILATE_BPP - 1); } } } @@ -76,18 +72,18 @@ void DilateImage(uint8_t *pImageBuff, int w, int h) void DilateImageSub(uint8_t *pImageBuff, int w, int h, int x, int y, int sw, int sh) { - const int BPP = 4; // RGBA assumed - uint8_t *apBuffer[2] = {NULL, NULL}; + uint8_t *apBuffer[2] = {nullptr, nullptr}; - apBuffer[0] = (uint8_t *)malloc((size_t)sw * sh * sizeof(uint8_t) * BPP); - apBuffer[1] = (uint8_t *)malloc((size_t)sw * sh * sizeof(uint8_t) * BPP); - uint8_t *pBufferOriginal = (uint8_t *)malloc((size_t)sw * sh * sizeof(uint8_t) * BPP); + const size_t ImageSize = (size_t)sw * sh * sizeof(uint8_t) * DILATE_BPP; + apBuffer[0] = (uint8_t *)malloc(ImageSize); + apBuffer[1] = (uint8_t *)malloc(ImageSize); + uint8_t *pBufferOriginal = (uint8_t *)malloc(ImageSize); for(int Y = 0; Y < sh; ++Y) { - int SrcImgOffset = ((y + Y) * w * BPP) + (x * BPP); - int DstImgOffset = (Y * sw * BPP); - int CopySize = sw * BPP; + int SrcImgOffset = ((y + Y) * w * DILATE_BPP) + (x * DILATE_BPP); + int DstImgOffset = (Y * sw * DILATE_BPP); + int CopySize = sw * DILATE_BPP; mem_copy(&pBufferOriginal[DstImgOffset], &pImageBuff[SrcImgOffset], CopySize); } @@ -99,16 +95,16 @@ void DilateImageSub(uint8_t *pImageBuff, int w, int h, int x, int y, int sw, int Dilate(sw, sh, apBuffer[1], apBuffer[0]); } - CopyColorValues(sw, sh, BPP, apBuffer[0], pBufferOriginal); + CopyColorValues(sw, sh, apBuffer[0], pBufferOriginal); free(apBuffer[0]); free(apBuffer[1]); for(int Y = 0; Y < sh; ++Y) { - int SrcImgOffset = ((y + Y) * w * BPP) + (x * BPP); - int DstImgOffset = (Y * sw * BPP); - int CopySize = sw * BPP; + int SrcImgOffset = ((y + Y) * w * DILATE_BPP) + (x * DILATE_BPP); + int DstImgOffset = (Y * sw * DILATE_BPP); + int CopySize = sw * DILATE_BPP; mem_copy(&pImageBuff[SrcImgOffset], &pBufferOriginal[DstImgOffset], CopySize); }