Windows XP SP3
Visual Studio 2008, VC++
Platform SDK (win32, no MFC etc.)
Hello, this is my first post here.
I have written something similar to a CAD for my own use that currently
uses
DirectX.
Most of the functions are implemented outside of DX and I basically just
use
it to render to the screen, zoom in and out and light the polygons.
All the geometry is sent to DX as individual triangles.
There are a couple of things that I want to do that the DX pipeline can't
do
(or does incorrectly) so I'm thinking of moving to OpenGL.
This is a huge task and I'm hoping that some of you can answer some
general
questions for me before I go wasting too much time in the wrong places.
1: I need to implement shadows. Without going into detail, at the moment I
create a volume shadow from each triangle and use a stencil buffer to
display it.
Is there a similar technique in OGL? (This has it's own problems when
rendering fog because the stencil is right at the front of the viewing
frustum, but at least I get ray traced shadows.)
2. Eventually would like to implement raytraced reflections and soft
shadows. Any advice on where to look at doing that?
I know that Blender (3d modelling) is open source and does it quite well.
Mine is not a commercial application and I can't afford to buy and
expensive
library.
3. I also need to render an off-centre window. In DX, I can do it with the
function D3DXMatrixPerspectiveOffCenterLH( );
It would be similar to rendering only a subsection of a scene. The camera
would be at (0,0,0) and aiming along the z axis, but the window would only
render a section off to the left or right. Is this possible?
I have more concerns, but these are the major ones.
Please let me know if there is a more appropriate newsgroup.
Any advice will be much appreciated.
Regards,
Ron Francis
www.RonaldFrancis.com
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