Refactor scrolling, added road tile, first sprites drawn but not implemented

testbed.c

@@ -461,25 +461,39 @@ typedef struct {
   unsigned int h;
   int scrollX;
   int scrollY;
-  unsigned int pageOffset;
-  unsigned char *tiles;
-} TilePage_t;
+  unsigned int pageOffset[2];
+  unsigned char currentPage;
+  unsigned int tilesOffset;
+  unsigned int *memTiles;
+  unsigned char *map;
+} TiledScreen_t;
 
-#define OFF_TILES 0x4840
+TiledScreen_t screen = { 0, 0, 0, 0, { 0x0400, 0x2620 }, 0, 0, NULL, NULL };
 
-void scrollPage(TilePage_t *page, int x, int y) {
-  x = min(max(x, 0), (page->w << 4) - 320);
-  y = min(max(y, 0), (page->h << 4) - 176);
-  page->scrollX = x;
-  page->scrollY = y;
+void loadTiles(unsigned int tilesOffset, unsigned int *memTiles) {
+  screen.tilesOffset = tilesOffset;
+  screen.memTiles = memTiles;
 }
 
-void drawPage(TilePage_t *page) {
-  unsigned int startX = page->scrollX >> 4;
-  unsigned int startY = page->scrollY >> 4;
-  unsigned int offsetX = page->scrollX - (startX << 4);
-  unsigned int offsetY = page->scrollY - (startY << 4);
-  unsigned int drawOffset = page->pageOffset;
+void loadMap(unsigned char *map, unsigned int w, unsigned int h) {
+  screen.map = map;
+  screen.w = w;
+  screen.h = h;
+}
+
+void scroll(int x, int y) {
+  x = min(max(x, 0), (screen.w << 4) - 320);
+  y = min(max(y, 0), (screen.h << 4) - 176);
+  screen.scrollX = x;
+  screen.scrollY = y;
+}
+
+void drawScreen() {
+  unsigned int startX = screen.scrollX >> 4;
+  unsigned int startY = screen.scrollY >> 4;
+  unsigned int offsetX = screen.scrollX - (startX << 4);
+  unsigned int offsetY = screen.scrollY - (startY << 4);
+  unsigned int drawOffset = screen.pageOffset[screen.currentPage];
   unsigned int scrollOffset = drawOffset + (offsetX >> 3) + (offsetY * PAGE_STRIDE);
   unsigned int x, y;
 
@@ -487,47 +501,44 @@ void drawPage(TilePage_t *page) {
 
   for (y = startY; y < startY + 13; y ++) {
     for (x = startX; x < startX + 21; x ++) {
-      blitTile(OFF_TILES + page->tiles[x + (y * page->w)], drawOffset);
+      blitTile(screen.tilesOffset + screen.map[x + (y * screen.w)], drawOffset);
       drawOffset += 2;
     }
     drawOffset += PAGE_STRIDE * 15;
   }
 
   setDisplayOffset(scrollOffset);
+  screen.currentPage ^= 1;
 }
 
 /*** S C R A T C H ***/
 
-unsigned char tiles[10000];
-TilePage_t pages[2] = {
-  { 100, 100, 0, 0, 0x0400, tiles },
-  { 100, 100, 0, 0, 0x2620, tiles }
-};
+unsigned int tiles[2*16 * 128];
+#define OFF_TILES 0x4840
 
-void fillTiles() {
+unsigned char map[10000];
+
+void fillMap() {
   unsigned int x, y, z;
   z = 0;
 
   for (y = 0; y < 100; y ++) {
     for (x = 0; x < 100; x ++) {
-      tiles[x + (y * 100)] = (((x + y + z) >> 2) % 3) << 5;
+      map[x + (y * 100)] = (((x + y + z) >> 2) % 4) << 5;
     }
   }
 }
 
-int main() {
+void game_init() {
   FILE *f;
   TifImageMeta_t meta;
-  int plane;
-  int x;
-  int y;
-  int z = 0;
-  unsigned int drawOffset;
-  unsigned int page = 0;
 
   setEGAMode();
   atexit(vid_cleanup);
 
+  tile_init();
+  fillMap();
+
   f = fopen("FOOTER.TIF", "rb");
   meta = tifLoadMeta(f);
   tifLoadEGA(f, meta, 0, 24, 336);
@@ -536,28 +547,35 @@ int main() {
   f = fopen("TILES.TIF", "rb");
   meta = tifLoadMeta(f);
   tifLoadEGA(f, meta, OFF_TILES, 256, 16);
+  tifLoad(f, meta, tiles, 128 * 16, 16);
   fclose(f);
 
-  kbd_init();
-  tile_init();
   setSplitScreen(351);
 
-  fillTiles();
+  loadTiles(OFF_TILES, tiles);
+  loadMap(map, 100, 100);
+  scroll(0, 0);
+}
+
+int main() {
+  int x;
+  int y;
+  int z = 0;
+
+  game_init();
+  kbd_init();
 
   while (!keyPressed(K_ESC)) {
-    page ^= 1;
 
-    x = pages[page].scrollX;
-    y = pages[page].scrollY;
-    if (keyPressed(K_LEFT))  x -= 4;
-    if (keyPressed(K_RIGHT)) x += 4;
-    if (keyPressed(K_UP))    y -= 4;
-    if (keyPressed(K_DOWN))  y += 4;
-    scrollPage(&pages[0], x, y);
-    scrollPage(&pages[1], x, y);
-    drawPage(&pages[page]);
+    x = screen.scrollX;
+    y = screen.scrollY;
+    if (keyPressed(K_LEFT))  x -= 8;
+    if (keyPressed(K_RIGHT)) x += 8;
+    if (keyPressed(K_UP))    y -= 8;
+    if (keyPressed(K_DOWN))  y += 8;
+    scroll(x, y);
+    drawScreen();
 
-//    kbd_wait();
     z++;
   }