;; Example 3-2 Using Modeling transformations (use gl) (use gl.glut) (define (init) (gl-clear-color 0.0 0.0 0.0 0.0) (gl-shade-model GL_FLAT) ) (define (draw-triangle) (gl-begin GL_LINE_LOOP) (gl-vertex '#f32(-20.0 -20.0)) (gl-vertex '#f32(20.0 -20.0)) (gl-vertex '#f32(0.0 14.6410161513775)) (gl-end)) (define (disp) (gl-clear GL_COLOR_BUFFER_BIT) (gl-load-identity) (gl-color '#f32(1.0 1.0 1.0)) (draw-triangle) (gl-enable GL_LINE_STIPPLE) (gl-line-stipple 1 #xf0f0) (gl-load-identity) (gl-translate -20.0 0.0 0.0) (draw-triangle) (gl-line-stipple 1 #xf00f) (gl-load-identity) (gl-scale 1.5 0.5 1.0) (draw-triangle) (gl-line-stipple 1 #x8888) (gl-load-identity) (gl-rotate 90.0 0.0 0.0 1.0) (draw-triangle) (gl-disable GL_LINE_STIPPLE) (gl-flush) ) (define (reshape w h) (gl-viewport 0 0 w h) (gl-matrix-mode GL_PROJECTION) (gl-load-identity) (gl-frustum -20.0 20.0 -20.0 20.0 1.5 20.0) (glu-look-at 0.0 0.0 5.0 0.0 0.0 0.0 0.0 1.0 0.0) (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)