scene:offscreen

(scene:offscreen &key width height background)

A viewer with no window: the same pipelines, the same camera and the same render function as scene:viewer, drawing into a texture scene:snapshot can read back. :width and :height are pixels. It has no input -- there is nothing to click -- so the camera moves through scene:camera and scene:fit, and a frame is scene:snapshot. This is what makes the renderer testable: no test may open a window, so without it the camera, the projection, the model matrices, the winding convention and the depth test would ship with nothing checking them. Part of the scene package: macOS only, never a .wasm. See the solid modeling guide.

CL-USER> (defvar *v* (scene:offscreen :width 320 :height 240))
CL-USER> (scene:add *v* (geom:box 200 :color (geom:vec3 1.0 0.2 0.2)))
CL-USER> (scene:fit *v*)
CL-USER> (length (scene:snapshot *v*))
307200