textures.c: clean up PNG reading

ps2homebrew · Feb 19, 2021 · 18835bf · 18835bf
1 parent cb8c2a3
commit 18835bf
Showing 1 changed file with 25 additions and 17 deletions.
diff --git a/src/textures.c b/src/textures.c
@@ -274,7 +274,7 @@ static void texPngReadMemFunction(png_structp pngPtr, png_bytep data, png_size_t
     *PngBufferPtr = (u8 *)(*PngBufferPtr) + length;
 }
 
-static void texPngReadPixels4(GSTEXTURE *texture, png_bytep *rowPointers)
+static void texPngReadPixels4(GSTEXTURE *texture, png_bytep *rowPointers, size_t size)
 {
     unsigned char *pixel = (unsigned char *)texture->Mem;
     png_clut_t *clut = (png_clut_t *)texture->Clut;
@@ -296,15 +296,19 @@ static void texPngReadPixels4(GSTEXTURE *texture, png_bytep *rowPointers)
         clut[i].alpha = pngTexture.trans[i] >> 1;
 
     for (i = 0; i < texture->Height; i++) {
-        for (j = 0; j < texture->Width / 2; j++) {
-            memcpy(&pixel[k], &rowPointers[i][1 * j], 1);
-            pixel[k] = (pixel[k] << 4) | (pixel[k] >> 4);
-            k++;
-        }
+        for (j = 0; j < texture->Width / 2; j++)
+            memcpy(&pixel[k++], &rowPointers[i][1 * j], 1);
     }
+
+    int byte;
+    unsigned char *tmpdst = (unsigned char *)texture->Mem;
+    unsigned char *tmpsrc = (unsigned char *)pixel;
+
+    for (byte = 0; byte < size; byte++)
+        tmpdst[byte] = (tmpsrc[byte] << 4) | (tmpsrc[byte] >> 4);
 }
 
-static void texPngReadPixels8(GSTEXTURE *texture, png_bytep *rowPointers)
+static void texPngReadPixels8(GSTEXTURE *texture, png_bytep *rowPointers, size_t size)
 {
     unsigned char *pixel = (unsigned char *)texture->Mem;
     png_clut_t *clut = (png_clut_t *)texture->Clut;
@@ -341,7 +345,7 @@ static void texPngReadPixels8(GSTEXTURE *texture, png_bytep *rowPointers)
     }
 }
 
-static void texPngReadPixels24(GSTEXTURE *texture, png_bytep *rowPointers)
+static void texPngReadPixels24(GSTEXTURE *texture, png_bytep *rowPointers, size_t size)
 {
     struct pixel3
     {
@@ -357,7 +361,7 @@ static void texPngReadPixels24(GSTEXTURE *texture, png_bytep *rowPointers)
     }
 }
 
-static void texPngReadPixels32(GSTEXTURE *texture, png_bytep *rowPointers)
+static void texPngReadPixels32(GSTEXTURE *texture, png_bytep *rowPointers, size_t size)
 {
     struct pixel
     {
@@ -375,7 +379,7 @@ static void texPngReadPixels32(GSTEXTURE *texture, png_bytep *rowPointers)
 }
 
 static void texPngReadData(GSTEXTURE *texture, png_structp pngPtr, png_infop infoPtr,
-                           void (*texPngReadPixels)(GSTEXTURE *texture, png_bytep *rowPointers))
+                           void (*texPngReadPixels)(GSTEXTURE *texture, png_bytep *rowPointers, size_t size))
 {
     int row, rowBytes = png_get_rowbytes(pngPtr, infoPtr);
     size_t size = gsKit_texture_size_ee(texture->Width, texture->Height, texture->PSM);
@@ -393,7 +397,7 @@ static void texPngReadData(GSTEXTURE *texture, png_structp pngPtr, png_infop inf
     }
     png_read_image(pngPtr, rowPointers);
 
-    texPngReadPixels(texture, rowPointers);
+    texPngReadPixels(texture, rowPointers, size);
 
     for (row = 0; row < texture->Height; row++)
         free(rowPointers[row]);
@@ -459,16 +463,19 @@ int texPngLoad(GSTEXTURE *texture, const char *path, int texId, short psm)
     png_get_IHDR(pngPtr, infoPtr, &pngWidth, &pngHeight, &bitDepth, &colorType, &interlaceType, NULL, NULL);
     texUpdate(texture, pngWidth, pngHeight);
 
-    if (colorType == PNG_COLOR_TYPE_GRAY)
-        png_set_expand(pngPtr);
-
     if (bitDepth == 16)
         png_set_strip_16(pngPtr);
 
+    if (colorType == PNG_COLOR_TYPE_GRAY || bitDepth < 4) {
+        png_set_expand(pngPtr);
+        if (png_get_valid(pngPtr, infoPtr, PNG_INFO_tRNS))
+            png_set_tRNS_to_alpha(pngPtr);
+    }
+
     png_set_filler(pngPtr, 0x80, PNG_FILLER_AFTER);
     png_read_update_info(pngPtr, infoPtr);
 
-    void (*texPngReadPixels)(GSTEXTURE * texture, png_bytep * rowPointers);
+    void (*texPngReadPixels)(GSTEXTURE * texture, png_bytep * rowPointers, size_t size);
     switch (png_get_color_type(pngPtr, infoPtr)) {
         case PNG_COLOR_TYPE_RGB_ALPHA:
             // if PNG have alpha, then it fits for every case (even if we only wanted RGB)
@@ -497,13 +504,14 @@ int texPngLoad(GSTEXTURE *texture, const char *path, int texId, short psm)
                 memset(texture->Clut, 0, gsKit_texture_size_ee(8, 2, GS_PSM_CT32));
 
                 texPngReadPixels = &texPngReadPixels4;
-            } else {
+            } else if (bitDepth == 8) {
                 texture->PSM = GS_PSM_T8;
                 texture->Clut = memalign(128, gsKit_texture_size_ee(16, 16, GS_PSM_CT32));
                 memset(texture->Clut, 0, gsKit_texture_size_ee(16, 16, GS_PSM_CT32));
 
                 texPngReadPixels = &texPngReadPixels8;
-            }
+            } else
+                return texPngEnd(pngPtr, infoPtr, file, ERR_BAD_DEPTH);
             break;
         default:
             return texPngEnd(pngPtr, infoPtr, file, ERR_BAD_DEPTH);