shader-pipeline: Accessing custom vertex attribute in shader

[afuzzyllama]

I have the follow custom vertex:

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...
driver->addVertexDescriptor("custom");
driver->getVertexDescriptor("custom")->addAttribute("inPosition",  3, irr::video::EVAS_POSITION,  irr::video::EVAT_FLOAT);
driver->getVertexDescriptor("custom")->addAttribute("inNormal",    3, irr::video::EVAS_NORMAL,    irr::video::EVAT_FLOAT);
driver->getVertexDescriptor("custom")->addAttribute("inColor",     4, irr::video::EVAS_COLOR,     irr::video::EVAT_UBYTE);
driver->getVertexDescriptor("custom")->addAttribute("inTexCoord0", 2, irr::video::EVAS_TEXCOORD0, irr::video::EVAT_FLOAT);
driver->getVertexDescriptor("custom")->addAttribute("inCustom",    3, irr::video::EVAS_CUSTOM,    irr::video::EVAT_FLOAT);
...
 

If I want to access "inCustom" in a shader:

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...
varying vec3 inCustom;
...
 

How can I do this in the shader pipeline branch?

[Nadro]

If you know how vertex structure looks you should use direct access eg.
YourVerticesStruct* vrt = Meshbuffer->getVertexBuffer()->getVertices();
vrt[0].InCustom = vector3df(1.f, 1.f, 1.f);
Of course you can use just vertex descriptor and offsets, but it's more complicate and slower solution. You should use offsets only in situation when you don't know how your format looks eg. you write universal method for some different vertex types.

[afuzzyllama]

Right, that is how you access the vertex information in C++, but how do you access the custom attribute in a shader language like GLSL?

[Nadro]

You should use 'attribute' for it. eg.
attribute vec3 inCustom;