DrawPrimitive Line Width (?)

You can use ID3DXLine.

DrawPrimitive does not support line widths. Your choices are:
1) D3DXLine (as mentioned above)
2) Roll your own by drawing a thin quad scaled appropriately

If I am working in 3D space am I bound to option #2 or can I still use ID3DXLine? It appears from the documentation ID3DXLine is for 2D only.

-Thanks again everyone!!!

A line is not a 3D object. You do not need lines, what you need are CYLINDERS.
That will help you out. If you would like to simulate laser rays, you will have to take some sprites / pixel shaded quads. There is no way to automaticaly draw a 3D Cylinder.

Even if D3DX Supports cylinders, it will Create a MESH with vertex & index buffer, so you can take a 3D model which is the same.

You can still "SCALE" a cylinder with matrix operations.

Quote:

Roll your own by drawing a thin quad scaled appropriately

That's funny, given that Direct3D doesn't even support quads :-)

Those are two of the most annoying problems when porting from OpenGL to D3D: no line width support, and no quads. But both a line, and a quad, really only are two triangles, so you can write adapter functions that do the right thing.

Quote:

Original post by hplus0603 Quote: Roll your own by drawing a thin quad scaled appropriately That's funny, given that Direct3D doesn't even support quads :-) Those are two of the most annoying problems when porting from OpenGL to D3D: no line width support, and no quads. But both a line, and a quad, really only are two triangles, so you can write adapter functions that do the right thing.

Sure D3D does, you just draw 2 triangles. D3D programmers can handle "complex" concepts like that. ;)

If you use the Quad primitive in OGL, you're just forcing the driver to do additional work since it needs to break them down to triangles anyway.

You can use the ID3DXLine::DrawTransform method to draw lines in 3D, but you need to provide it with (world*view*projection) transformation matrix.