OpenEuphoria

Re: To OpenGL gurus.

• Posted by 1evan at sbcglobal.net May 29, 2003
• 452 views

A clue perhaps?
If I change the parameters in glTranslatef so the first two are a 
positive value less than one and the third parameter equals 0, I get 
what looks like a rapidly vertically scrolling triangle.  Weirder yet is 
the fact that as I change the parameters, the color of the triangle changes.
My glTranslatef definition is: glTranslatef = link_c_proc(gl, 
"glTranslatef", {C_FLOAT,C_FLOAT,C_FLOAT})

Why are you using pfd = allocate(38)?  The PIXELFORMATDESCRIPTOR size is 
40.  I tried 38 and it didn't make any difference though.

xerox_irs at lvcm.com wrote:

>
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>Hears mine, the window is made by win32lib
>
>atom window_dc,g_hRC
>object junk
>global procedure init_opengl_window(atom id)
>        atom pfd,pixelformat
>        window_dc=getDC(id)
>        pfd=allocate(38)
>        mem_set(pfd,0,38)
>        poke4(pfd,38)--size
>        poke4(pfd+2,1)--version
>        poke4(pfd+4,or_all({PFD_DRAW_TO_WINDOW,  PFD_DOUBLEBUFFER ,
>PFD_SUPPORT_OPENGL}))--flags
>        poke(pfd+9,32)--color_bits
>        poke(pfd+23,32)--depth_bits
>        pixelformat=ChoosePixelFormat(window_dc,pfd)
>        junk= SetPixelFormat(window_dc, pixelformat, pfd)
>        g_hRC=wglCreateContext(window_dc)
>        junk= wglMakeCurrent(window_dc, g_hRC)
>end procedure
>
>
>>    c_proc(glClearDepth,{1.0})
>>    c_proc(gluPerspective,{45.0,width/height,0.1,100.0})
>>    
>>
>Increase Your ClearDepth to the last param of gluPerspective
>and
>  
>
>>    c_proc(glTranslatef, {-1.5,0.0,-6.0})
>>    
>>
>May put the puts the
>    c_proc(glVertex3f, {0.0,1.0,0.0})
>  
>
>>    c_proc(glColor3f, {0.0,1.0,0.0})
>>    c_proc(glVertex3f, {-1.0,-1.0,0.0})
>>    c_proc(glColor3f, {0.0,0.0,1.0})
>>    c_proc(glVertex3f, {1.0,-1.0,0.0})
>>    
>>
>Completly Less than z(0.1) or greater that z(1.0)--which should be 100.0
>
>That will do, I think
>Daniel Kluss
>
>----- Original Message ----- 
>From: <1evan at sbcglobal.net>
>To: "EUforum" <EUforum at topica.com>
>Sent: Wednesday, May 28, 2003 12:41 PM
>Subject: To OpenGL gurus.
>
>
>>I have pared down my program to its bare essentials, moving constant and
>>function definitions to include files.
>>The problem I am having now is that no GL objects are drawn to the
>>screen.  I'm guessing it has something to do with getting the rendering
>>context or device context.  I really don't know.
>>Any thoughts?
>>
>>include constants.ew  --for the windows functions and constants
>>include GLfunc.ew  --for the OpenGL functions
>>include GLconst.ew  --for the OpenGL constants
>>
>>atom glhRC, glhDC, hWnd, hInstance, ClassName, WindowRect
>>sequence keys keys = repeat(0,256)  -- array to hold key presses
>>
>>integer active, retval
>>active = TRUE
>>glhRC = NULL
>>glhDC = NULL
>>hWnd = NULL
>>hInstance = NULL
>>
>>procedure ReSizeGLScene(integer width, integer height)
>>    if height = 0 then
>>        height = 1  --prevent divide by 0
>>    end if
>>    c_proc(glViewport,{0,0,width,height})
>>    c_proc(glMatrixMode,{GL_PROJECTION})
>>    c_proc(glLoadIdentity,{})
>>    c_proc(gluPerspective,{45.0,width/height,0.1,100.0})
>>    c_proc(glMatrixMode,{GL_MODELVIEW})
>>    c_proc(glLoadIdentity,{})
>>end procedure
>>
>>procedure InitGL()
>>    c_proc(glShadeModel,{GL_SMOOTH})
>>    c_proc(glClearColor,{0.0,0.0,0.0,0.0})
>>    c_proc(glClearDepth,{1.0})
>>    c_proc(glEnable,{GL_DEPTH_TEST})
>>    c_proc(glDepthFunc,{GL_LEQUAL})
>>    c_proc(glHint,{GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST})
<snip>

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