material-maker/material_maker/tools/painter/shaders/paint_stamp.shader

74 lines
2.5 KiB
GLSL

shader_type canvas_item;
render_mode blend_disabled, unshaded;
uniform sampler2D tex2view_tex;
uniform float texture_size = 512.0;
uniform sampler2D seams : hint_white;
uniform float seams_multiplier = 256.0;
uniform sampler2D mesh_normal_tex;
uniform sampler2D layer_albedo_tex;
uniform sampler2D layer_mr_tex;
uniform sampler2D layer_emission_tex;
uniform sampler2D layer_depth_tex;
uniform bool erase = false;
uniform bool fill = false;
uniform float pressure = 1.0;
uniform vec2 brush_pos = vec2(0.5, 0.5);
uniform vec2 brush_ppos = vec2(0.5, 0.5);
uniform vec2 brush_size = vec2(0.25, 0.25);
uniform float brush_hardness = 0.5;
uniform float brush_opacity = 1.0;
uniform float stroke_length = 0.0;
uniform float stroke_angle = 0.0;
uniform float pattern_scale = 10.0;
uniform float pattern_angle = 0.0;
// BEGIN_PATTERN
float brush_function(vec2 uv) {
return clamp(max(0.0, 1.0-length(2.0*(uv-vec2(0.5)))) / (0.5), 0.0, 1.0);
}
uniform sampler2D brush_texture : hint_white;
vec4 pattern_function(vec2 uv) {
return texture(brush_texture, uv);
}
// END_PATTERN
float brush(vec2 uv) {
return clamp(brush_opacity*brush_function(uv)/(1.0-brush_hardness), 0.0, 1.0);
}
void fragment() {
// Get UV from seams texture
vec2 seams_value = texture(seams, UV).xy-vec2(0.5);
vec2 uv = fract(UV+seams_value*seams_multiplier/texture_size);
// Get View position
vec4 tex2view = texture(tex2view_tex, uv);
vec2 xy = tex2view.xy;
// Get distance to brush center
vec2 b = brush_pos/brush_size;
vec2 bv = (brush_ppos-brush_pos)/brush_size;
vec2 p = xy/brush_size;
float x = clamp(dot(p-b, bv)/dot(bv, bv), 0.0, 1.0);
// Get position in brush
vec2 local_uv = p-(b+x*bv);
mat2 texture_rotation = mat2(vec2(cos(pattern_angle), sin(pattern_angle)), vec2(-sin(pattern_angle), cos(pattern_angle)));
local_uv = texture_rotation*local_uv;
vec2 local_uv2 = p-b-bv;
local_uv2 = texture_rotation*local_uv2;
vec2 stamp_limit = step(abs(local_uv), vec2(1.0));
vec4 color = pattern_function(0.5*local_uv2+vec2(0.5));
float a = fill ? 1.0 : stamp_limit.x*stamp_limit.y*brush(0.5*local_uv+vec2(0.5))*color.a*tex2view.z;
vec4 screen_color = texture(SCREEN_TEXTURE, UV);
if (erase) {
COLOR = vec4(screen_color.xyz, max(screen_color.a-a, 0.0));
} else {
float alpha_sum = min(1.0, a + screen_color.a);
COLOR = vec4((color.xyz*a+screen_color.xyz*(vec3(alpha_sum)-a))/alpha_sum, alpha_sum);
}
}