3 replies to this topic

[db123]

I can render two-sided mesh by set the cullmode to CULL_None, but when i illuminate it by a spot light, there is some black place where the back-face is.

this is a screenshot with enable cull.


the following screenshot with disable cull. the white sign is the back face of this mesh.


I think the normal sampled from normal map is the normal for that pixel's reverse side, so my light can't illuminate it.

I wan't to know how to render the two-sided mesh with correct illumination, or get the correct normal for that pixel.


this is the mesh:

[Hodgman]

Which graphics API/shader language are you using?

Depending on the shader language, you can use gl_FrontFacing, VFACE or SV_IsFrontFace to tell you if the current pixel belongs to a front-face or a back-face. If you're shading a back-face, you can flip the normal.

[db123]

Hodgman, on 26 February 2012 - 12:55 AM, said:

Which graphics API/shader language are you using?

Depending on the shader language, you can use gl_FrontFacing, VFACE or SV_IsFrontFace to tell you if the current pixel belongs to a front-face or a back-face. If you're shading a back-face, you can flip the normal.

thank you, i use directx 11.

[db123]

Hodgman, on 26 February 2012 - 12:55 AM, said:

Which graphics API/shader language are you using?

Depending on the shader language, you can use gl_FrontFacing, VFACE or SV_IsFrontFace to tell you if the current pixel belongs to a front-face or a back-face. If you're shading a back-face, you can flip the normal.

it works well, thank you ~!!