Godot: is there a way for clipping planes?

[mohaalak]

I want to create simple water but I want to cut meshes , I konw that camera can do this but it will cut(clip) in the normal of camera , but I want to clip in in another rotation, is there any way to clip meshes , you can see water shader from here.
in this blog author using these code to clip

Vector3 planeNormalDirection = new Vector3(0, 0, 1);
planeNormalDirection.Normalize();
Vector4 planeCoefficients = new Vector4(planeNormalDirection, -waterHeight);
Matrix camMatrix = reflectionViewMatrix * projectionMatrix;
Matrix invCamMatrix = Matrix.Invert(camMatrix);
invCamMatrix = Matrix.Transpose(invCamMatrix);
planeCoefficients = Vector4.Transform(planeCoefficients, invCamMatrix);
Plane refractionClipPlane = new Plane(planeCoefficients);
device.ClipPlanes[0].Plane = refractionClipPlane;

[reduz]

no clipping planes in GLES2, and 3D engine will be rewritten this year, so not doing much more work for this

[reduz]

kicking to 3.1, where we might implement planar reflections

[akien-mga]

I guess it will have to wait again for the next milestone, as new rendering features are scheduled for when Vulkan support will be implemented.

[aaronfranke]

Vulkan support is now planned for 4.0

[io12]

It turns out that clipping planes can be emulated (with probably worse performance) using the discard keyword.

shader_type spatial;

uniform vec4 plane = vec4(1.0, 0.5, 0.0, 0.0);

bool culls(vec3 vertex, mat4 cam) {
    vec3 pos = (cam * vec4(vertex, 1.0)).xyz;
    return plane.x * pos.x
        + plane.y * pos.y
        + plane.z * pos.z
        + plane.w < 0.0;
}

void fragment() {
    if (culls(VERTEX, CAMERA_MATRIX)) {
        discard;
    }
    ALBEDO = vec3(1.0, 0.0, 0.0);
}

There's a video of this effect here: https://www.youtube.com/watch?v=9hiSy058-20

[SIsilicon]

That's great but, wouldn't that mean you'd have to apply that shader to _every_ geometry instance in the scene (or a selected few)?

[io12]

Yes, it's not a perfect solution

[akien-mga]

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