load tilemap from file

1 files changed, 77 insertions, 0 deletions

diff --git a/tiledfile.c b/tiledfile.c
new file mode 100644
index 0000000..8cb8dfa
--- /dev/null
+++ b/tiledfile.c
@@ -0,0 +1,77 @@
+#include <raylib.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+const int i = 1;
+#define is_bigendian() ( (*(char*)&i) == 0 )
+
+Texture2D processTilemapTexture(int * tilelayout, int width, int height) {
+    Color *pixels = (Color*) malloc(width * height * sizeof(Color));
+
+    for (int y = 0; y < height; y++) {
+        for (int x = 0; x < width; x++) {
+            int tile = tilelayout[y*width + x];
+            pixels[y*width + x] = (Color){
+                (int) tile, 0, 0, 0
+            };
+        }
+    }
+
+    Image checkedIm = {
+        .data = pixels,
+        .width = width,
+        .height = height,
+        .format = PIXELFORMAT_UNCOMPRESSED_R8G8B8A8,
+        .mipmaps = 1
+    };
+
+    Texture2D checked = LoadTextureFromImage(checkedIm);
+    UnloadImage(checkedIm);
+
+    return checked;
+}
+
+// read a big endian bytes from file
+int readb(char *out, size_t noBytes, FILE *file) {
+    int s = fread(out, (size_t)1, (size_t) noBytes, file);
+    
+    if (!is_bigendian()) {
+        int tmp;
+        // reverse byte order
+        for(int i = 0; i < noBytes/2; i++) {
+            tmp = out[i];
+            out[i] = out[noBytes-i-1];
+            out[noBytes-i-1] = tmp;
+        }
+    }
+    return s;
+}
+
+
+Texture2D loadTileMap(char *filename) {
+    int width, height, tilebytes;
+    int *tilelayout;
+
+    FILE *file;
+
+    file = fopen(filename, "rb");
+    // skip header 
+    fseek(file, 10, SEEK_CUR);
+    // 4 bytes for int width
+    readb((char *)&width, 4, file);
+    // 4 bytes for int height
+    readb((char *)&height, 4, file);
+    // 1 byte saying how big each tile is
+    readb((char *)&tilebytes, 4, file);
+    printf("tilebytes: %d\n", tilebytes);
+
+    tilelayout = malloc(width*height*tilebytes);
+    int tile;
+    for (int y = 0; y < height; y++) {
+        for (int x = 0; x < width; x++) {
+            readb((char *)&tile, tilebytes, file);
+            tilelayout[y*width + x] = tile;
+        }
+    }
+    return processTilemapTexture(tilelayout, width, height);
+}