#version 450
#extension GL_EXT_buffer_reference : require
#extension GL_EXT_buffer_reference_uvec2 : require

#include "hex_common.glsl"

layout(location=0) out vec4 color;

vec4 int2color(uint color_int) {
    float r = float((color_int >> 24) & 0xFF);
    float g = float((color_int >> 16) & 0xFF);
    float b = float((color_int >>  8) & 0xFF);
    float a = float((color_int >>  0) & 0xFF);
    return vec4(r, g, b, a)/255.0;
}

void main() {
  int region_index = gl_InstanceIndex/region_hex_count;
  Region region = pc.context.regions[region_index];
  if(uvec2(region) == uvec2(0)) {
    gl_Position = vec4(0, 0, 0, 0);
    return;
  }
  if(region.map != pc.context.current_map) {
    gl_Position = vec4(0, 0, 0, 0);
    return;
  }

  int hex_index = gl_InstanceIndex - (region_index*region_hex_count);
  vec2 region_qr = vec2(region.q, region.r);

  vec4 region_pos = vec4(0, 0, 0, 0);
  region_pos.x = (region_qr.x+region_qr.y/2)*region_width - region_qr.y*x/2;
  region_pos.z = 0.75*region_qr.y*region_height + 0.25*region_qr.y*z + 0.5*region_qr.x*z;

  float radius = 0;
  float ring = 0;
  int side = 0;
  if(hex_index != 0) {
    radius = floor(0.5 + sqrt(12*hex_index-3)/6);
    ring = hex_index - (3*radius*radius - 3*radius + 1);
    side = int(floor(ring/(radius)));
  } 

  vec4 position = vertices[indices[gl_VertexIndex]] + (starts[side]*radius) + (direction[side]*(ring-(radius*side))) + region_pos;
  if(gl_VertexIndex % 3 == 0) {
    position.y = (region.hexes[hex_index].heights[0] +
                  region.hexes[hex_index].heights[1] +
                  region.hexes[hex_index].heights[2] +
                  region.hexes[hex_index].heights[3] +
                  region.hexes[hex_index].heights[4] +
                  region.hexes[hex_index].heights[5])/6 + region.y;
  } else {
    position.y = region.hexes[hex_index].heights[indices[gl_VertexIndex]-1] + region.y;
  }
  color = int2color(region.hexes[hex_index].colors[indices[gl_VertexIndex]]);

  /*
  vec2 hex_qr = start_coords[side]*radius + direction_coords[side]*(ring-(radius*side));
  vec2 world_qr = vec2(0, 0); 
  world_qr.x = hex_qr.x
             + region_qr.x*((region_size-1)*2 + 1.0)
             + region_qr.y*((region_size-1)   + 0.0);

  world_qr.y = hex_qr.y
             - region_qr.x*((region_size-1)   + 0.5)
             - region_qr.y*((region_size-1)*2 + 1.0);

  color = vec4(world_qr/100, 0, 1);

  vec4 hex_pos = vec4(0, 0, 0, 1);
  hex_pos.x = x*hex_qr.x;
  hex_pos.z = -z*hex_qr.y - z*hex_qr.x/2;

  vec4 world_pos = vec4(0, 0, 0, 1);
  world_pos.x = hex_pos.x + region_pos.x;
  world_pos.z = hex_pos.z + region_pos.z;

  vec2 world_qr = vec2(0, 0);
  world_qr.x = world_pos.x/x;
  world_qr.y = -world_pos.z/z - world_pos.x/(2*x);
  */

  gl_Position = pc.context.proj * pc.context.view * position;
}