Hexagon pattern

A shader that generates a pattern of hexagons. It’s possible to modify:

* size

* spacing

* color

* transparency

Shader code
shader_type spatial;
render_mode unshaded;

uniform float scale = 8.0;
uniform float radius = 1.0;
uniform float offset = 0.268;
uniform float power = 1.0;
uniform bool hide_incomplete = false;
uniform vec4 color : hint_color = vec4(0.0, 0.6, 1.0, 1.0);

float is_in_hex(float hex_radius, vec2 local_point) {
	const vec2 AXIS[3] = {
		vec2(sqrt(3)*0.5, 0.5),
		vec2(0.0, 1.0),
		vec2(-sqrt(3)*0.5, 0.5)
	};
	float max_r = 0.0;
	for (int i = 0; i < 3; i++) {
		float r = dot(local_point, AXIS[i]);
		r /= (sqrt(3)*0.5*hex_radius);
		max_r = max(max_r, abs(r));
	}
	return max_r;
}

float snap_to_center(float local_coord, float hex_radius) {
	return float(floor((local_coord+hex_radius)/(2.0*hex_radius)))*2.0*hex_radius;
}

vec2 calculate_local_center(vec2 uv, float r) {
	float y_coord_1 = snap_to_center(uv.y, r);
	float x_coord_1 = snap_to_center(uv.x, r*sqrt(3));
	vec2 point_1 = vec2(x_coord_1, y_coord_1);
	
	float x_coord_2 = snap_to_center(uv.x - r*sqrt(3), r*sqrt(3));
	float y_coord_2 = snap_to_center(uv.y - r, r);
	vec2 point_2 = vec2(x_coord_2, y_coord_2) + vec2(r*sqrt(3), r);
	
	if (length(uv - point_1) < length(uv - point_2)) {
		return point_1;
	} else {
		return point_2;
	}
}

void fragment() {
	vec2 uv = (UV - vec2(0.5, 0.5)) * scale;
	float r = (radius * sqrt(3) + offset)/2.0;
	vec2 local_center = calculate_local_center(uv, r);
	vec2 local_coords = uv - local_center;
	
	if (hide_incomplete && (
			abs(local_center.x) > scale/2.0 - radius ||
			abs(local_center.y) > scale/2.0 - radius*sqrt(3)
		)
	) {
		ALPHA = 0.0;
	} else if (is_in_hex(radius, local_coords) <= 1.0) {
		float rad = is_in_hex(radius, local_coords);
		rad = pow(rad, power);
		ALBEDO = color.rgb;
		ALPHA = rad;
	} else {
		ALPHA = 0.0;
	}
}
Tags
hexagon, pattern
The shader code and all code snippets in this post are under CC0 license and can be used freely without the author's permission. Images and videos, and assets depicted in those, do not fall under this license. For more info, see our License terms.
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