with texture?

[Games28]

curious how would igo about doing the wave effect from this example in glsl with an imported mesh?
https://github.com/floooh/sokol-samples/blob/master/sapp/vertextexture-sapp.glsl

[floooh]

I think I'll need a couple more details for what you want to achieve. Load a 3D mesh and apply such a wooble effect? In general there's nothing sokol-specific about that, and I wouldn't base something like that on the above sample. Instead take a regular program which renders a 3D object, and then add some 'wobble effect' in the vertex shader.

The problem is usually that you'll need a highly tesselated 3D object to make the wobble look nice, and manually modelled 3D objects are usually optimized to reduce triangle count.

[Games28]

i would like to Load a 3D mesh and apply such a wooble effect. just not sure how the wooble effect is coded?

[floooh]

The demo uses a 2D simplex noise function (similar to Perlin noise), the noise is rendered into an offscreen pass into a texture (https://github.com/floooh/sokol-samples/blob/master/sapp/vertextexture-sapp.glsl#L3-L128), which is then sampled in a vertex shader to displace vertices in a 2D plane along the up-axis (and additionally pass the noise as color into the fragment shader: https://github.com/floooh/sokol-samples/blob/4439b99076b3e649d62afb3caed530e9a66448d3/sapp/vertextexture-sapp.glsl#L130-L153

But it's really just an adhoc effect to demonstrate sampling a texture in a vertex shader, not useful for the general case.

For a 3D mesh you'd want to displace along the vertex normal instead, but as I said above, unless the model is highly tesselated already it will probably look quite shitty.

As a starting point I would probably use a simple sinus wave for the displacement effect to distort the current vertex position in model space along the vertex normal, e.g. something like:

vec3 distorted_pos = pos + normal * sin(time) * scale;

...and then replace the sin() * scale with something more interesting.

[Games28]

where would this "vec3 distorted_pos = pos + normal * sin(time) * scale;" be use in vs or fs?

[floooh]

In the vertex shader.