How can I check existence of texture in shader programming?

Question

g_MeshTexture : texture file name

sampler MeshTextureSampler = 
sampler_state
{
    Texture = <g_MeshTexture>;
    MipFilter = LINEAR;
    MinFilter = LINEAR;
    MagFilter = LINEAR;
};

: sampler

I use "tex2D(MeshTextureSampler, In.TextureUV)"

Which condition in HLSL is similar to if(g_MeshTexture == NULL) in C++?

The HLSL equivalent is black pixels. No, really... there's no such thing. — Damon, Jul 02 '12 at 15:59
Then should I use flag in c++ code to check whether it has texture or not? — Gimun Eom, Jul 02 '12 at 16:08

score 2 · Answer 1 · answered Dec 04 '12 at 21:38

There's nothing built-in for HLSL to test this.

You can add an extra client-loaded parameter to tell the shader if the texture is valid or not, or create a second alternative shader that executes without that texture read in cases where the texture isn't deined (and assigned by the client C++ prog)

How can I check existence of texture in shader programming?

1 Answers1