#:use-module ((sdl2 render) #:prefix sdl2:)
#:use-module ((sdl2 surface) #:prefix sdl2:)
#:use-module (gl)
- #:export (bitmap
- move-xy))
+ #:export (image
+ move
+ scale
+ over))
-(define (bitmap filename)
+(define (calculate proc-or-value)
+ (if (procedure? proc-or-value)
+ (proc-or-value)
+ proc-or-value))
+
+(define (image filename)
(make-scene
- "bitmap"
+ "image"
(let ((image (sdl2:load-image filename))
(texture #f)
(w/2 0)
(h/2 0))
- (lambda* ()
+ (lambda ()
(when (not texture)
(set! texture (sdl2:surface->texture %sdl-renderer image))
(set! w/2 (/ (sdl2:surface-width image) 2))
(set! h/2 (/ (sdl2:surface-height image) 2)))
(gl-enable (oes-framebuffer-object texture-2d))
(sdl2:bind-texture texture)
+ (gl-enable (oes-framebuffer-object blend))
+ (set-gl-blend-function (blending-factor-src src-alpha)
+ (blending-factor-dest one-minus-src-alpha))
(gl-begin (begin-mode quads)
(gl-texture-coordinates 0 0)
(gl-vertex (- w/2) h/2 0)
(gl-vertex w/2 (- h/2) 0)
(gl-texture-coordinates 0 1)
(gl-vertex (- w/2) (- h/2) 0))
+ (gl-disable (oes-framebuffer-object blend))
(gl-disable (oes-framebuffer-object texture-2d))))))
-(define (move-xy x y scene)
- (define (to-integer n)
- (inexact->exact (round n)))
+(define* (move scene x y #:optional (z 0))
+ (make-scene
+ "move"
+ (lambda ()
+ (gl-translate (calculate x)
+ (calculate y)
+ (calculate z))
+ (display-scene scene))))
+
+(define* (scale scene x #:optional (y x) (z y))
+ (make-scene
+ "scale"
+ (lambda ()
+ (gl-scale (calculate x)
+ (calculate y)
+ (calculate z))
+ (display-scene scene))))
+
+(define (over . scenes)
(make-scene
- "move-xy"
+ "over"
(lambda ()
- (let ((xy (list (to-integer (if (procedure? x) (x) x))
- (to-integer (if (procedure? y) (y) y)))))
- (display-scene scene #:xy xy)))))
+ (let display ((sc scenes))
+ (cond ((not (null? sc))
+ (with-gl-push-matrix
+ (display-scene (car sc)))
+ (display (cdr sc))))))))