diff options
| -rw-r--r-- | sly/scene.scm | 120 |
1 files changed, 47 insertions, 73 deletions
diff --git a/sly/scene.scm b/sly/scene.scm index a06efd9..ddf8548 100644 --- a/sly/scene.scm +++ b/sly/scene.scm @@ -17,97 +17,71 @@ ;;; Commentary: ;; -;; Scene graph +;; Hierarchy of renderable objects using a directed acyclic graph +;; structure. ;; ;;; Code: (define-module (sly scene) #:use-module (ice-9 match) + #:use-module (srfi srfi-1) #:use-module (srfi srfi-9) #:use-module (srfi srfi-26) #:use-module (sly camera) - #:use-module (sly mesh) - #:use-module (sly quaternion) #:use-module (sly signal) - #:use-module (sly texture) #:use-module (sly transform) - #:use-module (sly transition) #:use-module (sly math vector) - #:export (scene-node - make-scene-node + #:use-module (sly render utils) + #:use-module (sly render renderer) + #:export (scene-node make-scene-node scene-node? - scene-node-transform scene-node-texture - scene-node-uniforms scene-node-children - update-scene-node draw-scene-node - make-scene - scene? - scene-root - update-scene draw-scene)) + scene-node-object scene-node-transform + scene-node-visible? scene-node-children + scene->render-list)) (define-record-type <scene-node> - (%make-scene-node transform texture uniforms children) + (%make-scene-node object transform visible? children) scene-node? + (object scene-node-object) (transform scene-node-transform) - (texture scene-node-texture) - (uniforms scene-node-uniforms) + (visible? scene-node-visible?) (children scene-node-children)) -(define* (make-scene-node #:optional #:key - (transform identity-transform) - (texture #f) - (uniforms '()) - (children '()) - #:allow-other-keys) - (match children - ((or (children ...) - (= list children)) - (%make-scene-node transform texture uniforms children)))) +(define* (make-scene-node #:optional object #:key (transform identity-transform) + (visible? #t) (children '())) + "Create a new scene node containing OBJECT, a renderable object that +responds to the 'draw' method. The node has a local transformation +matrix TRANSFORM, and a list of CHILDREN. The VISIBLE? flag etermines +whether to draw the node and all of its children or not." + (%make-scene-node object transform visible? children)) -(define-syntax-rule (scene-node (field val) ...) - (apply make-scene-node - (append (list (symbol->keyword 'field) val) ...))) +(define scene-node make-scene-node) -(define-syntax-rule (with-texture-maybe texture body ...) - (if (texture? texture) - (with-texture texture body ...) - (begin body ...))) +(define (flatten lst) + "Return a list that recursively concatenates all sub-lists of LIST." + (fold-right + (match-lambda* + (((sub-list ...) memo) + (append (flatten sub-list) memo)) + ((elem memo) + (cons elem memo))) + '() lst)) -(define* (draw-scene-node node alpha transform #:optional (uniforms '())) - (signal-let ((node node)) - (if (mesh? node) - (draw-mesh node `(("mvp" ,transform) - ,@uniforms)) - (signal-let ((children (scene-node-children node)) - (local-transform (scene-node-transform node)) - (texture (scene-node-texture node))) - (with-texture-maybe texture - (let ((transform (transform* transform local-transform)) - ;; FIXME: properly merge uniform alists together. - (uniforms (append uniforms (scene-node-uniforms node)))) - (for-each (cut draw-scene-node <> alpha transform uniforms) - children))))))) - -;;; -;;; Scene -;;; - -(define-record-type <scene> - (make-scene root cameras) - scene? - (root scene-root) - (cameras scene-cameras)) - -(define (update-scene scene) - "Update the nodes within SCENE." - (update-scene-node (scene-root scene))) - -(define (draw-scene scene alpha) - "Draw SCENE from the perspective of CAMERA with interpolation factor -ALPHA." - (for-each (lambda (camera) - (call-with-camera camera - (lambda (projection location) - (draw-scene-node (scene-root scene) - alpha - (transform* projection location))))) - (scene-cameras scene))) +(define (scene->render-list node) + "Traverse the scene graph defined by NODE and its children and +return a list of the render operations needed to display the scene. +Additionally, NODE or any of its children may be a signal to allow for +dynamic changes to the scene." + (define (iter node parent-transform) + (signal-let ((node node)) + (if (scene-node-visible? node) + (let ((transform (transform* parent-transform + (scene-node-transform node))) + (object (scene-node-object node))) + (cons (if object + (draw (scene-node-object node) transform) + '()) + (map (cut iter <> transform) + (scene-node-children node)))) + '()))) + (flatten (iter node identity-transform))) |