1 files changed, 6 insertions(+), 2 deletions(-)

M src/main.c

@@ 447,11 447,15 @@ particle_t* update_sand(uint8_t x, uint8_t y) {
         get_particle_material_id(get_particle(x, y + 1)) == MATERIAL_WATER_ID) {
       new_position.y = y + 1;
     } else if (get_particle_material_id(get_particle(x - 1, y + 1)) == MATERIAL_AIR_ID &&
-        get_particle_material_id(get_particle(x - 1, y)) == MATERIAL_AIR_ID) {
+        get_particle_material_id(get_particle(x - 1, y)) == MATERIAL_AIR_ID &&
+        x > 0
+        ) {
       new_position.x = x - 1;
       new_position.y = y + 1;
     } else if (get_particle_material_id(get_particle(x + 1, y + 1)) == MATERIAL_AIR_ID && 
-        get_particle_material_id(get_particle(x + 1, y)) == MATERIAL_AIR_ID) {
+        get_particle_material_id(get_particle(x + 1, y)) == MATERIAL_AIR_ID &&
+        x < CANVAS_WIDTH - 1
+        ) {
       new_position.x = x + 1;
       new_position.y = y + 1;
     }