al_draw_rotated_bitmap(3alleg5)                al_draw_rotated_bitmap(3alleg5)

       al_draw_rotated_bitmap - Allegro 5 API

              #include <allegro5/allegro.h>

              void al_draw_rotated_bitmap(ALLEGRO_BITMAP *bitmap,
                 float cx, float cy, float dx, float dy, float angle, int flags)

       Draws a rotated version of the given bitmap to the target bitmap.  The
       bitmap is rotated by 'angle' radians clockwise.

       The point at cx/cy relative to the upper left corner of the bitmap will
       be drawn at dx/dy and the bitmap is rotated around this point.  If
       cx,cy is 0,0 the bitmap will rotate around its upper left corner.

       · cx - center x (relative to the bitmap)

       · cy - center y (relative to the bitmap)

       · dx - destination x

       · dy - destination y

       · angle - angle by which to rotate (radians)

       · flags - same as for al_draw_bitmap(3alleg5)


              float w = al_get_bitmap_width(bitmap);
              float h = al_get_bitmap_height(bitmap);
              al_draw_rotated_bitmap(bitmap, w / 2, h / 2, x, y, ALLEGRO_PI / 2, 0);

       The above code draws the bitmap centered on x/y and rotates it 90°

       See al_draw_bitmap(3alleg5) for a note on restrictions on which bitmaps
       can be drawn where.

       al_draw_bitmap(3alleg5), al_draw_bitmap_region(3alleg5),
       al_draw_scaled_bitmap(3alleg5), al_draw_scaled_rotated_bitmap(3alleg5)

Allegro reference manual                       al_draw_rotated_bitmap(3alleg5)