foo

[gbajam22] / src / level.c

diff --git a/src/level.c b/src/level.c
index dfe3475..0ae8d3e 100644 (file)
--- a/src/level.c
+++ b/src/level.c
@@ -74,3 +74,29 @@ void free_level(struct level *lvl)
                free(tmp);
        }
 }
+
+void upd_vis(struct level *lvl, int32_t px, int32_t py, int32_t angle)
+{
+       int cx, cy;
+
+       lvl->numvis = 0;
+
+       pos_to_cell(px, py, &cx, &cy);
+
+       /* TODO: cont. */
+}
+
+void cell_to_pos(int cx, int cy, int32_t *px, int32_t *py)
+{
+       *px = cx * CELL_SIZE - (CELL_SIZE >> 1);
+       *py = cy * CELL_SIZE - (CELL_SIZE >> 1);
+}
+
+void pos_to_cell(int32_t px, int32_t py, int *cx, int *cy)
+{
+       _Static_assert((CELL_SIZE & ~0xff) == CELL_SIZE,
+                       "CELL_SIZE >> 8 in pos_to_cell will lose significant bits");
+
+       *cx = ((px + (CELL_SIZE >> 1)) << 8) / (CELL_SIZE >> 8);
+       *cy = ((py + (CELL_SIZE >> 1)) << 8) / (CELL_SIZE >> 8);
+}