Sync -num_tiles flags

tools/gbagfx/gfx.c

@@ -397,7 +397,7 @@ void ReadImage(char *path, int tilesWidth, int bitDepth, int metatileWidth, int
 	free(buffer);
 }
 
-void WriteImage(char *path, int numTiles, int bitDepth, int metatileWidth, int metatileHeight, struct Image *image, bool invertColors)
+void WriteImage(char *path, enum NumTilesMode numTilesMode, int numTiles, int bitDepth, int metatileWidth, int metatileHeight, struct Image *image, bool invertColors)
 {
 	int tileSize = bitDepth * 8;
 
@@ -424,7 +424,8 @@ void WriteImage(char *path, int numTiles, int bitDepth, int metatileWidth, int m
 		FATAL_ERROR("The specified number of tiles (%d) is greater than the maximum possible value (%d).\n", numTiles, maxNumTiles);
 
 	int bufferSize = numTiles * tileSize;
-	unsigned char *buffer = malloc(bufferSize);
+	int maxBufferSize = maxNumTiles * tileSize;
+	unsigned char *buffer = malloc(maxBufferSize);
 
 	if (buffer == NULL)
 		FATAL_ERROR("Failed to allocate memory for pixels.\n");
@@ -433,17 +434,36 @@ void WriteImage(char *path, int numTiles, int bitDepth, int metatileWidth, int m
 
 	switch (bitDepth) {
 	case 1:
-		ConvertToTiles1Bpp(image->pixels, buffer, numTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
+		ConvertToTiles1Bpp(image->pixels, buffer, maxNumTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
 		break;
 	case 4:
-		ConvertToTiles4Bpp(image->pixels, buffer, numTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
+		ConvertToTiles4Bpp(image->pixels, buffer, maxNumTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
 		break;
 	case 8:
-		ConvertToTiles8Bpp(image->pixels, buffer, numTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
+		ConvertToTiles8Bpp(image->pixels, buffer, maxNumTiles, metatilesWide, metatileWidth, metatileHeight, invertColors);
 		break;
 	}
 
-	WriteWholeFile(path, buffer, bufferSize);
+	bool zeroPadded = true;
+	for (int i = bufferSize; i < maxBufferSize && zeroPadded; i++) {
+		if (buffer[i] != 0)
+		{
+			switch (numTilesMode)
+			{
+			case NUM_TILES_IGNORE:
+				break;
+			case NUM_TILES_WARN:
+				fprintf(stderr, "Ignoring -num_tiles %d because tile %d contains non-transparent pixels.\n", numTiles, 1 + i / tileSize);
+				zeroPadded = false;
+				break;
+			case NUM_TILES_ERROR:
+				FATAL_ERROR("Tile %d contains non-transparent pixels.\n", 1 + i / tileSize);
+				break;
+			}
+		}
+	}
+
+	WriteWholeFile(path, buffer, zeroPadded ? bufferSize : maxBufferSize);
 
 	free(buffer);
 }

tools/gbagfx/gfx.h

@@ -44,8 +44,14 @@ struct Image {
 	bool isAffine;
 };
 
+enum NumTilesMode {
+    NUM_TILES_IGNORE,
+    NUM_TILES_WARN,
+    NUM_TILES_ERROR,
+};
+
 void ReadImage(char *path, int tilesWidth, int bitDepth, int metatileWidth, int metatileHeight, struct Image *image, bool invertColors);
-void WriteImage(char *path, int numTiles, int bitDepth, int metatileWidth, int metatileHeight, struct Image *image, bool invertColors);
+void WriteImage(char *path, enum NumTilesMode numTilesMode, int numTiles, int bitDepth, int metatileWidth, int metatileHeight, struct Image *image, bool invertColors);
 void FreeImage(struct Image *image);
 void ReadGbaPalette(char *path, struct Palette *palette);
 void WriteGbaPalette(char *path, struct Palette *palette);

tools/gbagfx/main.c

@@ -77,7 +77,7 @@ void ConvertPngToGba(char *inputPath, char *outputPath, struct PngToGbaOptions *
 
     ReadPng(inputPath, &image);
 
-    WriteImage(outputPath, options->numTiles, options->bitDepth, options->metatileWidth, options->metatileHeight, &image, !image.hasPalette);
+    WriteImage(outputPath, options->numTilesMode, options->numTiles, options->bitDepth, options->metatileWidth, options->metatileHeight, &image, !image.hasPalette);
 
     FreeImage(&image);
 }
@@ -179,6 +179,7 @@ void HandlePngToGbaCommand(char *inputPath, char *outputPath, int argc, char **a
     char *outputFileExtension = GetFileExtensionAfterDot(outputPath);
     int bitDepth = outputFileExtension[0] - '0';
     struct PngToGbaOptions options;
+    options.numTilesMode = NUM_TILES_IGNORE;
     options.numTiles = 0;
     options.bitDepth = bitDepth;
     options.metatileWidth = 1;
@@ -203,6 +204,12 @@ void HandlePngToGbaCommand(char *inputPath, char *outputPath, int argc, char **a
             if (options.numTiles < 1)
                 FATAL_ERROR("Number of tiles must be positive.\n");
         }
+        else if (strcmp(option, "-Wnum_tiles") == 0) {
+            options.numTilesMode = NUM_TILES_WARN;
+        }
+        else if (strcmp(option, "-Werror=num_tiles") == 0) {
+            options.numTilesMode = NUM_TILES_ERROR;
+        }
         else if (strcmp(option, "-mwidth") == 0)
         {
             if (i + 1 >= argc)

tools/gbagfx/options.h

@@ -4,6 +4,7 @@
 #define OPTIONS_H
 
 #include <stdbool.h>
+#include "gfx.h"
 
 struct GbaToPngOptions {
     char *paletteFilePath;
@@ -18,6 +19,7 @@ struct GbaToPngOptions {
 
 struct PngToGbaOptions {
     int numTiles;
+    enum NumTilesMode numTilesMode;
     int bitDepth;
     int metatileWidth;
     int metatileHeight;