// NOTE: DO NOT CHANGE THIS FILE. IT IS AUTOMATICALLY GENERATED.

#include <mbgl/shaders/collision_circle.hpp>

namespace mbgl {
namespace shaders {

const char* collision_circle::name = "collision_circle";
const char* collision_circle::vertexSource = R"MBGL_SHADER(
attribute vec2 a_pos;
attribute vec2 a_anchor_pos;
attribute vec2 a_extrude;
attribute vec2 a_placed;

uniform mat4 u_matrix;
uniform vec2 u_extrude_scale;
uniform float u_camera_to_center_distance;

varying float v_placed;
varying float v_notUsed;
varying float v_radius;

varying vec2 v_extrude;
varying vec2 v_extrude_scale;

void main() {
    vec4 projectedPoint = u_matrix * vec4(a_anchor_pos, 0, 1);
    highp float camera_to_anchor_distance = projectedPoint.w;
    highp float collision_perspective_ratio = 0.5 + 0.5 * (camera_to_anchor_distance / u_camera_to_center_distance);

    gl_Position = u_matrix * vec4(a_pos, 0.0, 1.0);

    highp float padding_factor = 1.2; // Pad the vertices slightly to make room for anti-alias blur
    gl_Position.xy += a_extrude * u_extrude_scale * padding_factor * gl_Position.w / collision_perspective_ratio;

    v_placed = a_placed.x;
    v_notUsed = a_placed.y;
    v_radius = abs(a_extrude.y); // We don't pitch the circles, so both units of the extrusion vector are equal in magnitude to the radius

    v_extrude = a_extrude * padding_factor;
    v_extrude_scale = u_extrude_scale * u_camera_to_center_distance / collision_perspective_ratio;
}

)MBGL_SHADER";
const char* collision_circle::fragmentSource = R"MBGL_SHADER(

varying float v_placed;
varying float v_notUsed;
varying float v_radius;
varying vec2 v_extrude;
varying vec2 v_extrude_scale;

void main() {
    float alpha = 0.5;

    // Red = collision, hide label
    vec4 color = vec4(1.0, 0.0, 0.0, 1.0) * alpha;

    // Blue = no collision, label is showing
    if (v_placed > 0.5) {
        color = vec4(0.0, 0.0, 1.0, 0.5) * alpha;
    }

    if (v_notUsed > 0.5) {
        // This box not used, fade it out
        color *= .2;
    }

    float extrude_scale_length = length(v_extrude_scale);
    float extrude_length = length(v_extrude) * extrude_scale_length;
    float stroke_width = 3.0;
    float radius = v_radius * extrude_scale_length;

    float distance_to_edge = abs(extrude_length - radius);
    float opacity_t = smoothstep(-stroke_width, 0.0, -distance_to_edge);

    gl_FragColor = opacity_t * color;
}

)MBGL_SHADER";

} // namespace shaders
} // namespace mbgl
