1 files changed, 89 insertions, 0 deletions
diff --git a/src/tools/dilate.cpp b/src/tools/dilate.cpp
new file mode 100644
index 00000000..b1b60ac3
--- /dev/null
+++ b/src/tools/dilate.cpp
@@ -0,0 +1,89 @@
+/* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */
+/* If you are missing that file, acquire a complete release at teeworlds.com.                */
+#include <base/system.h>
+#include <base/math.h>
+#include <engine/external/pnglite/pnglite.h>
+
+typedef struct
+{
+	unsigned char r, g, b, a;
+} CPixel;
+
+static void Dilate(int w, int h, CPixel *pSrc, CPixel *pDest)
+{
+	int ix, iy;
+	const int xo[] = {0, -1, 1, 0};
+	const int yo[] = {-1, 0, 0, 1};
+	
+	int m = 0;
+	for(int y = 0; y < h; y++)
+	{
+		for(int x = 0; x < w; x++, m++)
+		{
+			pDest[m] = pSrc[m];
+			if(pSrc[m].a)
+				continue;
+			
+			for(int c = 0; c < 4; c++)
+			{
+				ix = clamp(x + xo[c], 0, w-1);
+				iy = clamp(y + yo[c], 0, h-1);
+				int k = iy*w+ix;
+				if(pSrc[k].a)
+				{
+					pDest[m] = pSrc[k];
+					pDest[m].a = 255;
+					break;
+				}
+			}
+		}
+	}
+}
+
+static void CopyAlpha(int w, int h, CPixel *pSrc, CPixel *pDest)
+{
+	int m = 0;
+	for(int y = 0; y < h; y++)
+		for(int x = 0; x < w; x++, m++)
+			pDest[m].a = pSrc[m].a;
+}
+
+int main(int argc, char **argv)
+{
+	png_t Png;
+	CPixel *pBuffer[3] = {0,0,0};
+	
+	png_init(0, 0);
+	png_open_file(&Png, argv[1]);
+	
+	if(Png.color_type != PNG_TRUECOLOR_ALPHA)
+	{
+		dbg_msg("dilate", "not an RGBA image");
+		return -1;
+	}
+	
+	pBuffer[0] = (CPixel*)mem_alloc(Png.width*Png.height*sizeof(CPixel), 1);
+	pBuffer[1] = (CPixel*)mem_alloc(Png.width*Png.height*sizeof(CPixel), 1);
+	pBuffer[2] = (CPixel*)mem_alloc(Png.width*Png.height*sizeof(CPixel), 1);
+	png_get_data(&Png, (unsigned char *)pBuffer[0]);
+	png_close_file(&Png);
+	
+	int w = Png.width;
+	int h = Png.height;
+	
+	Dilate(w, h, pBuffer[0], pBuffer[1]);
+	for(int i = 0; i < 5; i++)
+	{
+		Dilate(w, h, pBuffer[1], pBuffer[2]);
+		Dilate(w, h, pBuffer[2], pBuffer[1]);
+	}
+	
+	CopyAlpha(w, h, pBuffer[0], pBuffer[1]);
+	
+	// save here
+	png_open_file_write(&Png, argv[1]);
+	png_set_data(&Png, w, h, 8, PNG_TRUECOLOR_ALPHA, (unsigned char *)pBuffer[1]);
+	png_close_file(&Png);
+	
+	return 0;
+}