From ac4433a899dbc7292e47b839cc17c0d502097fde Mon Sep 17 00:00:00 2001
From: Robin Krens <robin@robinkrens.nl>
Date: Sun, 12 Jun 2022 16:36:17 +0200
Subject: [PATCH] tools: bmp2tiles swan_gfx_t struct + function call changes

---
 tools/bmp2tiles/bmp2tiles.c | 86 +++++++++++++++++++++++++--------------------
 1 file changed, 48 insertions(+), 38 deletions(-)

diff --git a/tools/bmp2tiles/bmp2tiles.c b/tools/bmp2tiles/bmp2tiles.c
index 25ea7d5..472442a 100644
--- a/tools/bmp2tiles/bmp2tiles.c
+++ b/tools/bmp2tiles/bmp2tiles.c
@@ -9,6 +9,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <string.h>
 #include <SDL2/SDL_image.h>
 
@@ -16,46 +17,48 @@
 #define FOURBBP_ROW	8
 #define FOURBPP_COL	8
 
-void bmp_info(SDL_Surface * img)
-{
-	SDL_PixelFormat * fmt;
-	fmt = img->format;
-	fprintf(stdout,"WIDTH: %d, HEIGHT: %d, BPP: %d\n", img->w, img->h, fmt->BitsPerPixel);
-}
+typedef struct {
+	unsigned width;
+	unsigned height;
+	unsigned bpp;
+} swan_gfx_t;
 
-
-void generate_4bpp_tile_planar(unsigned char *buf, void * userdata, int sz)
+void set_info(swan_gfx_t * gfx, SDL_Surface * img)
 {
-	unsigned char * ptr = (unsigned char *) userdata;
-	for (int i = 0; i < 32; i+=4) {
-		/* fprintf(stdout, "userdata: pos: %d - %d\n", i, *ptr++); */
-		for (int j = 0; j < 4; ++j) {
-			for (int x = 0; x < 8; ++x) {
-				buf[i + j] = ptr[x] << j; 
-			}
-			/* printf("%d: %x\n", i+j, buf[i+j]); */
-		}
-		ptr += 8;
-	}
+	gfx->width = img->w;
+	gfx->height = img->h;
+	gfx->bpp = img->format->BitsPerPixel;
+	
+	/* set userdata to iterate */
+	SDL_LockSurface(img);
+	img->userdata = img->pixels;
+	SDL_UnlockSurface(img);
 }
 
-void generate_4bpp_tile_packed(unsigned char *buf, void * userdata, int sz)
+void generate_4bpp_tile(unsigned char *buf, void * userdata, 
+		bool packed)
 {
 	unsigned char * ptr = (unsigned char *) userdata;
-	for (int i = 0; i < 32; i+=4) {
+	for (int i = 0; i < TILE_SZ; i+=4) {
 		for (int j = 0; j < 4; ++j) {
-			buf[i+j] = ptr[0] << 4;
-			buf[i+j] |= ptr[1];
-			ptr += 2;
-			printf("%d: %x\n", i+j, buf[i+j]);
+			if (packed) { /* packed format */
+				buf[i+j] = ptr[0] << 4;
+				buf[i+j] |= ptr[1];
+				ptr += 2;
+			} else { /* planar format */
+				for (int x = 0; x < 8; ++x) {
+					buf[i + j] = ptr[x] << j; 
+				}
+			}
 		}
+		if (!packed)
+			ptr += 8;
 	}
 }
 
 int main(void)
 {
 	SDL_Surface * rawbmp;
-	SDL_PixelFormat * fmt;
 	FILE * ostream;
 	char filename[] = "test.bmp";
 	char outname[] = "test.gfx";
@@ -66,18 +69,16 @@ int main(void)
 		exit(EXIT_FAILURE);
 	}
 
-	bmp_info(rawbmp);
-
-	SDL_LockSurface(rawbmp);
-	rawbmp->userdata = rawbmp->pixels;
-	SDL_UnlockSurface(rawbmp);
+	swan_gfx_t * gfx = malloc(sizeof(swan_gfx_t));
+	set_info(gfx, rawbmp);
 
 	unsigned char *tile_buf = malloc(sizeof(unsigned char) * TILE_SZ);
 	
-	/* if (rawbmp->format->BitsPerPixel != 24) {
-		fprintf(stderr, "format %d not supported\n", rawbmp->format->BitsPerPixel);
+	if (gfx->bpp != 8) {
+		fprintf(stderr, "warning: %d bpp format detected\n", rawbmp->format->BitsPerPixel);
+		fprintf(stderr, "use --force in command to run\n");
 		exit(EXIT_FAILURE);
-	} */
+	}
 
 	ostream = fopen(outname, "w");
 	if (!ostream) {
@@ -85,10 +86,19 @@ int main(void)
 		exit(EXIT_FAILURE);
 	}
 
-	generate_4bpp_tile_packed(tile_buf, rawbmp->userdata, 64);
-	int ret = fwrite(tile_buf, sizeof(unsigned char), 32, ostream);	
-	printf("written: %d\n", ret);
+	unsigned nr_tiles = 1;
 
-	SDL_FreeSurface(rawbmp);
+	for (int i = 0; i < nr_tiles; ++i) {
+		generate_4bpp_tile(tile_buf, rawbmp->userdata, true);
+		int ret = fwrite(tile_buf, sizeof(unsigned char), TILE_SZ, ostream);
+		if (ret != TILE_SZ) {
+			fprintf(stderr, "failed to convert, only write %d instead of %d\n", ret, TILE_SZ);
+			goto cleanup;
+		}
+	}
 
+cleanup:
+	free(gfx);
+	SDL_FreeSurface(rawbmp);
+	fclose(ostream);
 }
-- 
2.7.4