Texture with mipmapping has artifacts when zoomed out

Help Shaders
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1

Godot Version

4.4.1

Question

I’m not sure if this is a Godot error or just how graphics cards work, but I’m noticing that my mipmapped texture has obvious artifacts when you sample around 50x. I would expect at this zoom out level that the mipmap would be just returning a single pixel that is the average of the entire image, but instead I’m getting something that doesn’t look mipmapped at all.

shader_type canvas_item;
render_mode blend_mix;

uniform float uv_scalar = 1.0;
uniform sampler2D tex: repeat_enable;

void fragment() {
	COLOR = texture(tex, UV * uv_scalar);
}

This is really obvious when you zoom in and out because instead of a smooth transition, artifacts from the texture jump all around the image.

Shader with uv_scalar = 100:

image
image216×213 5.38 KB

Same texture zoomed in a bit

image
image378×391 15.8 KB

Zoomed in more

image
image317×342 3.49 KB

Zoomed in close enough to see the base texture

image
image202×192 5.2 KB

The texture is set to generate mipmaps, but they don’t seem to be doing much good:

image
image266×657 25.4 KB

Is there a way to get a smooth zoom in/out on this shader?

2

mipmaps are enabled but the texture is not set to sample mipmaps, use the hint filter_linear_mipmap

uniform sampler2D tex: repeat_enable, filter_linear_mipmap;