diff options
| -rw-r--r-- | chickadee/graphics/buffer.scm | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/chickadee/graphics/buffer.scm b/chickadee/graphics/buffer.scm index 9e5a791..40ebce8 100644 --- a/chickadee/graphics/buffer.scm +++ b/chickadee/graphics/buffer.scm @@ -50,6 +50,7 @@ apply-buffer map-buffer! unmap-buffer! + resize-buffer! with-mapped-buffer make-buffer-view make-streaming-buffer-view @@ -89,7 +90,7 @@ buffer? (id buffer-id) (name buffer-name) - (length buffer-length) + (length buffer-length set-buffer-length!) (stride buffer-stride) (target buffer-target) (usage buffer-usage) @@ -142,7 +143,7 @@ (define* (make-buffer data #:key (name "anonymous") - (length (bytevector-length data)) + (length (if data (bytevector-length data) 0)) (offset 0) (stride 0) (target 'vertex) @@ -224,6 +225,24 @@ vertex buffer data back to the GPU." (gl-unmap-buffer (buffer-target-gl buffer)) (set-buffer-data! buffer #f)) +(define (resize-buffer! buffer length) + "Resize BUFFER to LENGTH bytes, preserving all existing mapped data +that that fits into the resized buffer. Only streaming buffers can be +resized." + (if (eq? (buffer-usage buffer) 'stream) + ;; Remap the buffer and copy old contents + (let ((old-bv (buffer-data buffer))) + (set-buffer-length! buffer length) + (when old-bv + (unmap-buffer! buffer) + ;; TODO: Set map mode in record + (map-buffer! buffer 'write-only) + (let ((new-bv (buffer-data buffer))) + (bytevector-copy! old-bv 0 new-bv 0 + (min (bytevector-length old-bv) + (bytevector-length new-bv)))))) + (error "cannot resize static buffer"))) + (define-syntax-rule (with-mapped-buffer buffer body ...) (dynamic-wind (lambda () |