diff options
| -rw-r--r-- | chickadee/graphics/model.scm | 102 |
1 files changed, 64 insertions, 38 deletions
diff --git a/chickadee/graphics/model.scm b/chickadee/graphics/model.scm index 5746e5a..2fe7131 100644 --- a/chickadee/graphics/model.scm +++ b/chickadee/graphics/model.scm @@ -103,7 +103,7 @@ (mesh model-node-mesh) (matrix model-node-matrix) (world-matrix model-node-world-matrix) - (children model-node-children)) + (children model-node-children set-model-node-children!)) (define* (make-model-node #:key (name "anonymous") @@ -114,20 +114,20 @@ (%make-model-node name mesh matrix world-matrix children)) (define (draw-model-node node state view-matrix camera-position skybox lights) - (for-each (lambda (child) - (draw-model-node child state view-matrix camera-position - skybox lights)) - (model-node-children node)) - (let ((mesh (model-node-mesh node))) - (when mesh - (render-state-world-model-matrix-mult! state - (model-node-world-matrix node)) - (draw-mesh mesh - #:model-matrix (render-state-world-model-matrix state) - #:view-matrix view-matrix - #:camera-position camera-position - #:skybox skybox - #:lights lights)))) + (match node + (($ <model-node> name mesh matrix world-matrix children) + (for-each (lambda (child) + (draw-model-node child state view-matrix camera-position + skybox lights)) + children) + (when mesh + (render-state-world-model-matrix-mult! state world-matrix) + (draw-mesh mesh + #:model-matrix (render-state-world-model-matrix state) + #:view-matrix view-matrix + #:camera-position camera-position + #:skybox skybox + #:lights lights))))) ;;; @@ -961,7 +961,7 @@ (weights (number-array-ref/optional obj "weights"))) ;; TODO: Support weights. (make-mesh name primitives))) - (define (parse-node obj parse-child parent-matrix meshes) + (define (parse-node obj meshes) ;; TODO: Parse all fields of nodes. (let* ((name (or (string-ref/optional obj "name") "anonymous")) ;; TODO: Parse camera. @@ -987,36 +987,62 @@ (match translation (#(x y z) (matrix4-translate (vec3 x y z)))))))) - (world-matrix (matrix4* matrix parent-matrix)) (mesh (match (number-ref/optional obj "mesh") (#f #f) (n (vector-ref meshes n)))) ;; TODO: Parse weights. - (weights #f) - (children (map (lambda (i) - (parse-child i world-matrix)) - (vector->list - (or (array-ref/optional obj "children") - #()))))) + (weights #f)) (make-model-node #:name name - #:children children #:matrix matrix - #:world-matrix world-matrix #:mesh mesh))) (define (parse-nodes array meshes) - (define nodes (make-vector (vector-length array) #f)) - (define (parse-node* i matrix) - (let ((node (vector-ref nodes i))) - (or node - (let ((node (parse-node (vector-ref array i) - parse-node* - matrix - meshes))) - (vector-set! nodes i node) - node)))) - (for-range ((i (vector-length array))) - (parse-node* i (make-identity-matrix4))) - nodes) + (let* ((k (vector-length array)) + (nodes (make-vector k))) + ;; Creating the node tree is a multi-phase process. First, we + ;; parse all of the nodes in order, ignoring children since the + ;; array is not guaranteed to be topologically sorted and the + ;; child nodes may not exist yet. Then, we take another pass to + ;; initialize children now that all nodes can be referenced. + ;; Next, we topologically sort the nodes and initialize world + ;; matrices. The topological sort ensures that we initialize the + ;; matrices of parents before their children. + (for-range ((i k)) + (vector-set! nodes i (parse-node (vector-ref array i) meshes))) + (for-range ((i k)) + (let ((node (vector-ref nodes i)) + (children (or (array-ref/optional (vector-ref array i) "children") + #()))) + (set-model-node-children! node (map (lambda (j) + (vector-ref nodes j)) + (vector->list children))))) + (let ((visited (make-hash-table)) + (top-nodes '())) + (define (visit node) + (match (hashq-ref visited node) + (#f + (hashq-set! visited node 'temp) + (for-each visit (model-node-children node)) + (hashq-set! visited node 'perm) + (set! top-nodes (cons node top-nodes))) + ('temp (error "cycle in glTF node tree")) + ('perm #t))) + (for-range ((i k)) + (visit (vector-ref nodes i))) + ;; Reuse the visited table for world matrix initialization. + (hash-clear! visited) + (define (init-world-matrix node parent-matrix) + (match node + (($ <model-node> name mesh matrix world-matrix children) + (matrix4-mult! world-matrix parent-matrix matrix) + (hashq-set! visited node #t) + (for-each (lambda (child) + (init-world-matrix child world-matrix)) + children)))) + (for-each (lambda (node) + (unless (hashq-ref visited node) + (init-world-matrix node (make-identity-matrix4)))) + top-nodes)) + nodes)) (define (parse-scene obj nodes) (let ((name (or (string-ref/optional obj "name") "anonymous")) (children |