I hauled the sgl-hello-world program (attached below) into drrracket, version 7.6, english by PLT.
I click on 'run'I click on 'run'. It creates a small window containing a small white square. I click on 'run' again. It deetes that window, and creates another small window containing a small white square. I click on 'run' again. It deetes that window, and creates another small window containing a small white square. I click on 'run' again. It deetes that window, and creates another small window containing a small white square. etc. After about 35 runs, the new small window instead contains a large white square filling the entire window. Evidently, something happens after multiple runs. Perhaps spme resource is exhausted Perhaps it's random and might happen after a hundred runs another time? I don't know. But I'm having similarly erratic behaviour in a far more complicated program, and this is the simplest version of erraticity I've found so far. This code was found on the Racket users mailing list archives. -- hendrik -------------- #lang racket/gui ; This code from https://groups.google.com/forum/#!topic/racket-users/-84bgybC3C0 ; -- hendrik (require (lib "gl.ss" "sgl") (lib "gl-vectors.ss" "sgl") ) (define (resize w h) (glViewport 0 0 w h) #t ) (define (draw-opengl) (glClearColor 0.0 0.0 0.0 0.0) (glClear GL_COLOR_BUFFER_BIT) (glColor3d 1.0 1.0 1.0) (glMatrixMode GL_PROJECTION) (glLoadIdentity) (glOrtho 0.0 1.0 0.0 1.0 -1.0 1.0) (glMatrixMode GL_MODELVIEW) (glLoadIdentity) (glBegin GL_QUADS) (glVertex3d 0.25 0.25 0.0) (glVertex3d 0.75 0.25 0.0) (glVertex3d 0.75 0.75 0.0) (glVertex3d 0.25 0.75 0.0) (glEnd) ) (define my-canvas% (class* canvas% () (inherit with-gl-context swap-gl-buffers) (define/override (on-paint) (with-gl-context (lambda () (draw-opengl) (swap-gl-buffers) ) ) ) (define/override (on-size width height) (with-gl-context (lambda () (resize width height) ) ) ) (super-instantiate () (style '(gl))) ) ) (define win (new frame% (label "OpenGl Test") (min-width 200) (min-height 200))) (define gl (new my-canvas% (parent win))) (send win show #t) ; It should be pretty easy to tweak it. ; Hope this helps, ; Laurent ; - show quoted text - ; - show quoted text - ; _________________________________________________ ; For list-related administrative tasks: ; http://lists.racket-lang.org/listinfo/users -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/20200816133219.ln7ameblw7pvpnxo%40topoi.pooq.com.
