Adaptive Outline

This is a vanilla shader with a stroke.

The stroke brightens the light areas and darkens the dark areas.

шейдер изменём только в final.fsh

version 330 compatibility

uniform sampler2D colortex0;
uniform sampler2D depthtex0;

in vec2 texcoord;
layout(location = 0) out vec4 color;

void main() {
vec2 texel = 1.0 / vec2(textureSize(colortex0, 0));
vec4 scene = texture(colortex0, texcoord);

float d_center = 1.0 - textureLod(depthtex0, texcoord, 0.0).r;

vec2 offsets[2] = vec2[](
vec2(texel.x, 0),
vec2(texel.x * 3.0, 0)
);

float gradients[4];

for(int i = 0; i < 2; i++) {
float d_right = 1.0 - textureLod(depthtex0, texcoord + offsets[i], 0.0).r;
float d_left = 1.0 - textureLod(depthtex0, texcoord - offsets[i], 0.0).r;

gradients[i] = abs(d_right - d_left) / (offsets[i].x * 2.0);

vec2 vertical_offset = vec2(0, offsets[i].x);
float d_up = 1.0 - textureLod(depthtex0, texcoord + vertical_offset, 0.0).r;
float d_down = 1.0 - textureLod(depthtex0, texcoord - vertical_offset, 0.0).r;

gradients[i + 2] = abs(d_up - d_down) / (vertical_offset.y * 2.0);
}

float gradient_ratio_h = gradients[0] / (gradients[1] + 0.0001);
float gradient_ratio_v = gradients[2] / (gradients[3] + 0.0001);

bool is_real_edge_h = gradient_ratio_h > 2.0;
bool is_real_edge_v = gradient_ratio_v > 2.0;

float edge = 0.0;

if(is_real_edge_h || is_real_edge_v) {
float max_gradient = max(gradients[0], gradients[2]);
edge = max_gradient * 500.0;
}

float depth_precision = 0.001 + d_center * 0.01;
if(edge < depth_precision * 100.0) {
edge = 0.0;
}

float threshold = 0.15;

if(edge > threshold && (is_real_edge_h || is_real_edge_v)) {
float edge_strength = clamp((edge - threshold) * 2.0, 0.0, 1.0);

vec4 color_up = texture(colortex0, texcoord + vec2(0, texel.y));
vec4 color_down = texture(colortex0, texcoord - vec2(0, texel.y));
vec4 color_left = texture(colortex0, texcoord - vec2(texel.x, 0));
vec4 color_right = texture(colortex0, texcoord + vec2(texel.x, 0));

vec4 avg_color = (color_up + color_down + color_left + color_right) * 0.25;

float neighbor_brightness = dot(avg_color.rgb, vec3(0.299, 0.587, 0.114));

float brightness_factor;

if(neighbor_brightness > 0.35) { // here we change the change threshold
brightness_factor = 1.0 + edge_strength * 0.2; // we're changing it here brightens
} else {
brightness_factor = 1.0 - edge_strength * 0.2; // we're changing it here darkens
}

color.rgb = scene.rgb * brightness_factor;
color.a = scene.a;

} else {
color = scene;
}
}