I found 'alpha.ss' a helpful example Stephen #lang scheme/gui ;; By Brendan Burns ;; on Jaunty install the libgl1-mesa-dev package or make the symbolic links yourself ;; /usr/lib$ sudo ln -s libGL.so.1 libGL.so ;; /usr/lib$ sudo ln -s libGLU.so.1 libGLU.so ;; Standard requires (require sgl/gl "gl-frame.ss") ;; texture ;; This needs to be here and not in gl-init because of some weirdness in the ;; threading on windows causes the window to attempt to be drawn prior to the ; texture being fully loaded. (define *texture* (image->gl-vector (get-file "Choose image for texture" #f "../../icons" "sk" "jpg" null '(("Image" "*.jpg"))))) ;; Init function (define (my-gl-init) (let ((res *texture*)) ;; Same texture, three smoothing styles... (init-textures 3) (unless (gl-load-texture (list-ref res 2) (list-ref res 0) (list-ref res 1) GL_NEAREST GL_NEAREST 0) (error "Couldn't load texture")) (unless (gl-load-texture (list-ref res 2) (list-ref res 0) (list-ref res 1) GL_LINEAR GL_LINEAR 1) (error "Couldn't load texture")) (unless (gl-load-texture (list-ref res 2) (list-ref res 0) (list-ref res 1) GL_LINEAR GL_LINEAR_MIPMAP_NEAREST 2) (error "Couldn't load texture")) ;; Set-up alpha blending 50% transparency (glColor4d 1 1 1 0.5) (glBlendFunc GL_SRC_ALPHA GL_ONE) (glEnable GL_BLEND) ;; Standard Init (glEnable GL_TEXTURE_2D) (glShadeModel GL_SMOOTH) (glClearColor 0.0 0.0 0.0 0.5) (glClearDepth 1) (glEnable GL_DEPTH_TEST) (glDepthFunc GL_LEQUAL) (glHint GL_PERSPECTIVE_CORRECTION_HINT GL_NICEST) ;; default light (glEnable GL_LIGHT0) (glEnable GL_LIGHTING))) ;; Our user interaction variables (define *xrot* 0) (define *yrot* 0) (define *zrot* 0) (define *z* -5) (define *blend* #f) (define *tex* 0) ;; Our main function that does the drawing (define (my-gl-draw) ;; erase the background (glClear (+ GL_COLOR_BUFFER_BIT GL_DEPTH_BUFFER_BIT)) ;; turn blending on/off (if *blend* (glEnable GL_BLEND) (glDisable GL_BLEND)) ;; draw cube. (glLoadIdentity) (glTranslated 0 0 *z*) (glRotated *xrot* 1 0 0) (glRotated *yrot* 0 1 0) (glRotated *zrot* 0 0 1) (glBindTexture GL_TEXTURE_2D (get-texture *tex*)) (glBegin GL_QUADS) ; front (glNormal3d 0 0 1) (glTexCoord2i 0 0) (glVertex3i -1 -1 1) (glTexCoord2i 1 0) (glVertex3i 1 -1 1) (glTexCoord2i 1 1) (glVertex3i 1 1 1) (glTexCoord2i 0 1) (glVertex3i -1 1 1) ; back (glNormal3d 0 0 -1) (glTexCoord2i 1 0) (glVertex3i -1 -1 -1) (glTexCoord2i 1 1) (glVertex3i 1 -1 -1) (glTexCoord2i 0 1) (glVertex3i 1 1 -1) (glTexCoord2i 0 0) (glVertex3i -1 1 -1) ; top (glNormal3d 0 1 0) (glTexCoord2i 0 1) (glVertex3i -1 1 -1) (glTexCoord2i 0 0) (glVertex3i 1 1 -1) (glTexCoord2i 1 0) (glVertex3i 1 1 1) (glTexCoord2i 1 1) (glVertex3i -1 1 1) ; bottom (glNormal3d 0 -1 0) (glTexCoord2i 1 1) (glVertex3i -1 -1 -1) (glTexCoord2i 0 1) (glVertex3i -1 -1 1) (glTexCoord2i 0 0) (glVertex3i 1 -1 1) (glTexCoord2i 1 0) (glVertex3i 1 -1 -1) ; right (glNormal3d 1 0 0) (glTexCoord2i 1 0) (glVertex3i 1 -1 -1) (glTexCoord2i 1 1) (glVertex3i 1 -1 1) (glTexCoord2i 0 1) (glVertex3i 1 1 1) (glTexCoord2i 0 0) (glVertex3i 1 1 -1) ;left (glNormal3d -1 0 0) (glTexCoord2i 0 0) (glVertex3i -1 -1 -1) (glTexCoord2i 1 0) (glVertex3i -1 1 -1) (glTexCoord2i 1 1) (glVertex3i -1 1 1) (glTexCoord2i 0 1) (glVertex3i -1 -1 1) (glEnd) (set! *xrot* (+ *xrot* 0.3)) (set! *yrot* (+ *yrot* 0.2)) (set! *zrot* (+ *zrot* 0.4)) (glFlush)) ;; Move forward (add-key-mapping #\i (lambda () (set! *z* (+ *z* 0.3)))) ;; Move backward (add-key-mapping #\k (lambda () (set! *z* (- *z* 0.3)))) ;; Turn blending on/off (add-key-mapping #\b (lambda () (set! *blend* (not *blend*)))) ;; Cycle textures (add-key-mapping #\t (lambda () (set! *tex* (modulo (+ *tex* 1) 3)))) ;; Set the init function (set-gl-init-fn my-gl-init) ;; Set the draw function (set-gl-draw-fn my-gl-draw) (gl-run) <div class="gmail_quote">On Mon, Jan 18, 2010 at 7:50 PM, Eduardo Bellani <<a href="mailto:ebellani@gmail.com">ebellani@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div class="im">> First, some of the GLUT functions are implemented in the sgl library. > Search for glu on the C style API page. > > It seems like you're main problem is starting up a canvas and getting > a GL-context. > > Attached is a short example with your code based on my gl-world package. > > Jay </div>Thanks man! Now I do have a working canvas, at least. Do you have any clue as to why it does not visible draw anything? From what I'm seeing, the C and the scheme versions are somewhat equivalent, except for the resize and all the GLUT calls. -- <div><div></div><div class="h5">Eduardo Bellani <a href="http://www.cnxs.com.br" target="_blank">www.cnxs.com.br</a> More is not better (or worse) than less, just different. – The paradigm paradox. _________________________________________________ For list-related administrative tasks: <a href="http://list.cs.brown.edu/mailman/listinfo/plt-scheme" target="_blank">http://list.cs.brown.edu/mailman/listinfo/plt-scheme</a> </div></div></blockquote></div> -- -- Stephen De Gabrielle <a href="mailto:stephen.degabrielle@acm.org">stephen.degabrielle@acm.org</a> Telephone +44 (0)20 85670911 Mobile +44 (0)79 85189045 <a href="http://www.degabrielle.name/stephen">http://www.degabrielle.name/stephen</a>