Vertexdeclarations

Graphics and GPU Programming Programming

Started by Keba May 16, 2005 01:23 PM

4 comments, last by Keba 18 years, 11 months ago

170

Author

May 16, 2005 01:23 PM

Hello, Is vertexdeclataionens software depended or hardware depended. To clarify, if i got an old GFX card, but DX9 would this support VertexDeclaratons, or only FVF? i mean vertexdeclarations isn't hardware depended rather software depended(which version on DirectX) right? could i create a program that creates a VB with VertexDeclarations and then use it to render(no shader effect or something like that) with an old GFX card? by old GFX card, meaning something like GF4MX....a card thats dosen't support shaders... thanks

dave

2,188

May 16, 2005 01:24 PM

I think vertex declarations have existed since Vertex Buffers have existed. I don't think you have to worry about it at all these days.

I could easily be wrong though.

ace

Keba

170

Author

May 16, 2005 01:25 PM

god you were fast!
that is what i call a fast answer :P...almost under a minut :D
so the VertexDeclarations isn't bounded to shaders in any way?

circlesoft

1,178

May 16, 2005 01:34 PM

(1) Vertex declarations have existed since D3D9. In D3D8 and below, FVF's (flexible vertex formats) are used exclusively. Vertex decls were added because they allow a lot more control when it comes to informing D3D of your vertex structure. And since shaders are becoming more and more widespread, we need that.

(2) Vertex decls are a software-side thing. Any DX9 app can use them, regardless of the hardware (including GF4MX 420-440).

(3) A vertex declaration informs D3D of your vertex structure and format. It uses this to make sure that the shader input matches your structure. Vertex decls are bound to shaders, because the vertex format must match the input of the vertex shader.