shader_type spatial;
render_mode depth_draw_always;
uniform bool is_link = false;
uniform bool is_focus_from = false;
uniform bool is_focus_to = false;
uniform vec3 focus_min_from = vec3(0,0,0);
uniform vec3 focus_max_from = vec3(0,0,0);
uniform vec3 focus_min_to = vec3(0,0,0);
uniform vec3 focus_max_to = vec3(0,0,0);
uniform float focus_rate = 1.0;
uniform bool is_target = false;
uniform vec3 target_position = vec3(0, 1.28, 1);
varying vec3 world_position;

uniform vec2 pixel_size = vec2(0.02, 0.02);

void vertex()
{
	world_position = (MODEL_MATRIX * vec4(VERTEX, 1.0)).xyz;
}

bool is_in_focus(vec3 f_min,vec3 f_max){
    if(world_position.x<f_min.x||world_position.x>f_max.x){return false;}
    if(world_position.z>f_max.z){return false;}
    if(world_position.y>f_max.y && world_position.z>f_min.z){return false;}
    return true;
}

void fragment() {
    if(!is_link){
        if(is_focus_from || is_focus_to){
            bool is_in_focus_from = is_in_focus(focus_min_from,focus_max_from);
            bool is_in_focus_to = is_in_focus(focus_min_to,focus_max_to);
            if(is_in_focus_from&&is_in_focus_to){
                ALPHA = 1.0;
            }
            else if(is_focus_to&&is_in_focus_to){
                //ALPHA = focus_rate;
                ALPHA = 1.0;
            }
            else if(is_focus_from&&is_in_focus_from){
                //ALPHA = 1.0 - focus_rate;
                discard;
            }else{
                discard;
            }
        }
    }

    vec3 c = COLOR.rgb;
    float brightness = 1.0;
    if(is_target){
        float offset_y = abs(floor((world_position.y-target_position.y) / 0.02) * 0.02);
        offset_y = max(0.0,offset_y-0.64);
        float rate = clamp(1.0-offset_y/4.48,0.0,1.0);
        brightness = rate;
    }else{
        brightness = 1.0;
    }
    vec3 world_normal = (INV_VIEW_MATRIX * vec4(NORMAL, 0.0)).xyz;
    if(world_normal.y<0.1){
        brightness = brightness*0.6;
    }
    c.rgb = mix(vec3(0.0), c.rgb, brightness);
	ALBEDO = c.rgb;
}