Re: [wxhaskell-users] Where is the sample programm of wxHaskell OpenGL canvas using the HOpenGL binding?

[shelarcy <she...@ca...>]

On Sat, 3 Apr 2004 12:29:31 +0200, Daan Leijen <daa...@xs...> 
wrote:
> I haven't used it myself as I haven't been able to get HOpenGL
> (the haskell binding to openGL) working yet on my windows machine.
>
> As such, using openGL with wxHaskell is still a bit experimental
> terrain. The best thing you can do is to ask Sean Seefried if you
> can send you his code so that you can see a specific example.
>
> The technology though is pretty straightforward: just create an
> openGL canvas and activate it -- after that, all openGL commands
> are directed to that window, whether you use HOpenGL or other
> openGL code.

I asked him show the simplist example, and I understood how to
work this.

I wrote redbook example, and I checked it out.
Thank you for you and him.

But I don't understand everything yet, so this isn't complete work.
Hide Window Once, then you see work it.


module Main
where

import Data.List ( transpose )
import Graphics.UI.WX
import Graphics.UI.WXCore
import qualified Graphics.Rendering.OpenGL as GL
import Graphics.Rendering.OpenGL

main = start gui


defaultWidth  = 500
defaultHeight = 500

gui = do
     f <- frame [ text := "Simple OpenGL" ]
     glCanvas <- glCanvasCreateEx f 0 (Rect 0 0 defaultWidth defaultHeight)
          0 "GLCanvas" [GL_RGBA] nullPalette
     let glWidgetLayout = (fill . widget) glCanvas
     Graphics.UI.WX.set f [ layout := glWidgetLayout
                          , on paint := paintGL
                          ]


ctrlPoints :: [[Vertex3 GLfloat]]
ctrlPoints = [
     [ Vertex3 (-1.5) (-1.5)   4.0,  Vertex3 (-0.5) (-1.5)   2.0,
       Vertex3   0.5  (-1.5) (-1.0), Vertex3   1.5  (-1.5)   2.0 ],
     [ Vertex3 (-1.5) (-0.5)   1.0,  Vertex3 (-0.5) (-0.5)   3.0,
       Vertex3   0.5  (-0.5)   0.0,  Vertex3   1.5  (-0.5) (-1.0) ],
     [ Vertex3 (-1.5)   0.5    4.0,  Vertex3 (-0.5)   0.5    0.0,
       Vertex3   0.5    0.5    3.0,  Vertex3   1.5    0.5    4.0 ],
     [ Vertex3 (-1.5)   1.5  (-2.0), Vertex3 (-0.5)   1.5  (-2.0),
       Vertex3   0.5    1.5    0.0,  Vertex3   1.5    1.5  (-1.0) ]]

initlights :: IO ()
initlights = do
     lighting $= Enabled
     light (Light 0) $= Enabled

     ambient  (Light 0) $= Color4 0.2 0.2 0.2 1.0
     GL.position (Light 0) $= Vertex4 0 0 2 1

     materialDiffuse   Front $= Color4 0.6 0.6 0.6 1.0
     materialSpecular  Front $= Color4 1.0 1.0 1.0 1.0
     materialShininess Front $= 50

myInit :: IO ()
myInit = do
     clearColor $= Color4 0 0 0 0
     depthFunc $= Just Less
     m <- newMap2 (0, 1) (0, 1) (transpose ctrlPoints)
     map2 $= Just (m :: GLmap2 Vertex3 GLfloat)
     autoNormal $= Enabled
     mapGrid2 $= ((20, (0, 1)), (20, (0, 1 :: GLfloat)))
     initlights  -- for lighted version only

display = do
     clear [ ColorBuffer, DepthBuffer ]
     preservingMatrix $ do
        rotate (85 :: GLfloat) (Vector3 1 1 1)
        evalMesh2 Fill (0, 20) (0, 20)
     flush

reshape size@(GL.Size w h) = do
     viewport $= (Position 0 0, size)
     matrixMode $= Projection
     loadIdentity
     let wf = fromIntegral w
         hf = fromIntegral h
     if w <= h
        then ortho (-4.0) 4.0 (-4.0*hf/wf) (4.0*hf/wf) (-4.0) 4.0
        else ortho (-4.0*wf/hf) (4.0*wf/hf) (-4.0) 4.0 (-4.0) 4.0
     matrixMode $= Modelview 0
     loadIdentity

convWG (Graphics.UI.WX.Size w h) = (GL.Size (convInt32  w) (convInt32  h))
convInt32 = fromInteger . toInteger

paintGL :: DC() -> Graphics.UI.WX.Rect -> IO ()
paintGL dc rect = do
     -- write your commands to do OpenGL things here.
     myInit
     display
     reshape $ convWG $ rectSize rect
     return ()


-- 
shelarcy <she...@ca...>
http://page.freett.com/shelarcy/