22 lines
620 B
GLSL
22 lines
620 B
GLSL
shader_type canvas_item;
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uniform sampler2D brush_texture : hint_albedo;
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uniform vec2 brush_pos = vec2(0.5, 0.5);
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uniform vec2 brush_ppos = vec2(0.5, 0.5);
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uniform vec2 brush_size = vec2(0.25, 0.25);
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uniform float brush_strength = 0.5;
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float brush(float v) {
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return clamp(v / (1.0-brush_strength), 0.0, 1.0);
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}
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void fragment() {
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vec2 b = brush_pos/brush_size;
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vec2 bv = (brush_ppos-brush_pos)/brush_size;
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vec2 p = UV/brush_size;
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float x = clamp(dot(p-b, bv)/dot(bv, bv), 0.0, 1.0);
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float a = 1.0-length(p-(b+x*bv));
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a = brush(max(0.0, a));
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COLOR = vec4(vec3(1.0), 0.5*a);
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}
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