diff options
Diffstat (limited to '2d/sprite.scm')
| -rw-r--r-- | 2d/sprite.scm | 53 |
1 files changed, 36 insertions, 17 deletions
diff --git a/2d/sprite.scm b/2d/sprite.scm index a4a0719..21e27de 100644 --- a/2d/sprite.scm +++ b/2d/sprite.scm @@ -30,6 +30,7 @@ #:use-module ((sdl sdl) #:prefix SDL:) #:use-module (2d animation) #:use-module (2d helpers) + #:use-module (2d math) #:use-module (2d texture) #:use-module (2d gl) #:use-module (2d vector)) @@ -204,12 +205,14 @@ bound." (tex-coords (sprite-texture-coords sprite))) (%sprite-batch-draw *sprite-batch* texture - (- (vx pos) (vx anchor)) - (- (vy pos) (vy anchor)) + (vx pos) + (vy pos) (vx size) (vy size) #:color (sprite-color sprite) #:rotation (sprite-rotation sprite) + #:origin-x (vx anchor) + #:origin-y (vy anchor) #:scale-x (vx scale) #:scale-y (vy scale) #:u (first tex-coords) @@ -302,46 +305,62 @@ bound." (%make-sprite-batch max-size 0 #f (make-packed-array sprite-vertex (* 4 max-size)))) (define (sprite-batch-draw . args) - "Adds a textured quad to the sprite batch." + "Adds a textured quad to the current zsprite batch." (apply %sprite-batch-draw *sprite-batch* args)) -(define* (%sprite-batch-draw batch texture x y width height - #:optional #:key - (scale-x 1) (scale-y 1) (rotation 0) - (u 0) (v 0) (u2 1) (v2 1) - (color #xffffffff)) +(define* (%sprite-batch-draw batch texture x y width height #:optional #:key + (origin-x 0) (origin-y 0) (scale-x 1) (scale-y 1) + (rotation 0) (u 0) (v 0) (u2 1) (v2 1) + (color #xffffffff)) "Adds a textured quad to the sprite batch." ;; Render the batch when it's full or the texture changes. (cond ((= (sprite-batch-size batch) (sprite-batch-max-size batch)) (sprite-batch-render batch)) ((not (equal? texture (sprite-batch-texture batch))) (sprite-batch-switch-texture batch texture))) - ;; Add 4 new vertices. + + ;; Add 4 new vertices, taking into account scaling and rotation. (let* ((base (* 4 (sprite-batch-size batch))) (vertices (sprite-batch-vertices batch)) (color (rgba->gl-color color)) - (x2 (+ x width)) - (y2 (+ y height)) + (sin (sin-degrees rotation)) + (cos (cos-degrees rotation)) + (world-origin-x (+ origin-x x)) + (world-origin-y (+ origin-y y)) + (local-x1 (* (- origin-x) scale-x)) + (local-y1 (* (- origin-y) scale-y)) + (local-x2 (* (- width origin-x) scale-x)) + (local-y2 (* (- height origin-y) scale-y)) + (x1 (+ world-origin-x (- (* cos local-x1) (* sin local-y1)))) + (y1 (+ world-origin-y (* sin local-x1) (* cos local-y1))) + (x2 (+ world-origin-x (- (* cos local-x1) (* sin local-y2)))) + (y2 (+ world-origin-y (* sin local-x1) (* cos local-y2))) + (x3 (+ world-origin-x (- (* cos local-x2) (* sin local-y2)))) + (y3 (+ world-origin-y (* sin local-x2) (* cos local-y2))) + (x4 (+ x1 (- x3 x2))) + (y4 (- y3 (- y2 y1))) (r (vector-ref color 0)) (g (vector-ref color 1)) (b (vector-ref color 2)) (a (vector-ref color 3))) + ;; Vertices go counter clockwise, starting from the top-left + ;; corner. (pack vertices base sprite-vertex - x y + x1 y1 r g b a u v) (pack vertices (+ base 1) sprite-vertex - x2 y + x2 y2 r g b a - u2 v) + u v2) (pack vertices (+ base 2) sprite-vertex - x2 y2 + x3 y3 r g b a u2 v2) (pack vertices (+ base 3) sprite-vertex - x y2 + x4 y4 r g b a - u v2)) + u2 v)) ;; Increment batch size (set-sprite-batch-size! batch (1+ (sprite-batch-size batch)))) |