;; Example 3-5 Wireframe Sphere with Two Clipping Planes (use gl) (use gl.glut) (define (init) (gl-clear-color 0.0 0.0 0.0 0.0) (gl-shade-model GL_FLAT) ) (define (disp) (gl-clear GL_COLOR_BUFFER_BIT) (gl-color '#f32(1.0 1.0 1.0)) (gl-push-matrix) (gl-translate 0.0 0.0 -5.0) (gl-clip-plane GL_CLIP_PLANE0 '#f64(0.0 1.0 0.0 0.0)) (gl-enable GL_CLIP_PLANE0) (gl-clip-plane GL_CLIP_PLANE1 '#f64(1.0 0.0 0.0 0.0)) (gl-enable GL_CLIP_PLANE1) (gl-rotate 90.0 1.0 0.0 0.0) (glut-wire-sphere 1.0 20 16) (gl-pop-matrix) (gl-flush) ) (define (reshape w h) (gl-viewport 0 0 w h) (gl-matrix-mode GL_PROJECTION) (gl-load-identity) (glu-perspective 60.0 (/ w h) 1.0 20.0) (gl-matrix-mode GL_MODELVIEW) ) (define (keyboard key x y) (when (= key 27) (exit 0))) (define (main args) (glut-init args) (glut-init-display-mode (logior GLUT_SINGLE GLUT_RGB)) (glut-init-window-size 500 500) (glut-init-window-position 100 100) (glut-create-window *program-name*) (init) (glut-display-func disp) (glut-reshape-func reshape) (glut-keyboard-func keyboard) (glut-main-loop) 0)