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// NOTE: DO NOT CHANGE THIS FILE. IT IS AUTOMATICALLY GENERATED.
#include <mbgl/shaders/collision_box.hpp>
namespace mbgl {
namespace shaders {
const char* collision_box::name = "collision_box";
const char* collision_box::vertexSource = R"MBGL_SHADER(
attribute vec2 a_pos;
attribute vec2 a_anchor_pos;
attribute vec2 a_extrude;
attribute vec2 a_data;
uniform mat4 u_matrix;
uniform float u_scale;
uniform float u_pitch;
uniform float u_collision_y_stretch;
uniform float u_camera_to_center_distance;
varying float v_max_zoom;
varying float v_placement_zoom;
varying float v_perspective_zoom_adjust;
varying vec2 v_fade_tex;
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 = 1.0 + 0.5 * ((camera_to_anchor_distance / u_camera_to_center_distance) - 1.0);
highp float incidence_stretch = camera_to_anchor_distance / (u_camera_to_center_distance * cos(u_pitch));
highp float collision_adjustment = max(1.0, incidence_stretch / u_collision_y_stretch);
gl_Position = u_matrix * vec4(a_pos + a_extrude * collision_perspective_ratio * collision_adjustment / u_scale, 0.0, 1.0);
v_max_zoom = a_data.x;
v_placement_zoom = a_data.y;
v_perspective_zoom_adjust = floor(log2(collision_perspective_ratio * collision_adjustment) * 10.0);
v_fade_tex = vec2((v_placement_zoom + v_perspective_zoom_adjust) / 255.0, 0.0);
}
)MBGL_SHADER";
const char* collision_box::fragmentSource = R"MBGL_SHADER(
uniform float u_zoom;
// u_maxzoom is derived from the maximum scale considered by the CollisionTile
// Labels with placement zoom greater than this value will not be placed,
// regardless of perspective effects.
uniform float u_maxzoom;
uniform sampler2D u_fadetexture;
// v_max_zoom is a collision-box-specific value that controls when line-following
// collision boxes are used.
varying float v_max_zoom;
varying float v_placement_zoom;
varying float v_perspective_zoom_adjust;
varying vec2 v_fade_tex;
void main() {
float alpha = 0.5;
// Green = no collisions, label is showing
gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0) * alpha;
// Red = collision, label hidden
if (texture2D(u_fadetexture, v_fade_tex).a < 1.0) {
gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0) * alpha;
}
// Faded black = this collision box is not used at this zoom (for curved labels)
if (u_zoom >= v_max_zoom + v_perspective_zoom_adjust) {
gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0) * alpha * 0.25;
}
// Faded blue = the placement scale for this label is beyond the CollisionTile
// max scale, so it's impossible for this label to show without collision detection
// being run again (the label's glyphs haven't even been added to the symbol bucket)
if (v_placement_zoom >= u_maxzoom) {
gl_FragColor = vec4(0.0, 0.0, 1.0, 1.0) * alpha * 0.2;
}
}
)MBGL_SHADER";
} // namespace shaders
} // namespace mbgl
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