uniform mat4 modelViewProjectionMatrix;
uniform mat4 modelViewMatrix;
uniform sampler2DRect particles0;
uniform sampler2DRect particles1;
uniform sampler2DRect particles2;
uniform sampler2DRect particles3;
uniform sampler2DRect particles4; // prev
uniform sampler2DRect particles5; // org

uniform int uEnergy;

in vec4  position;
in vec2  texcoord;

out vec2 vTexCoord;
out vec3 vPos;
out vec4 vTarget;
out float vTemperature;
out float vAge;
out vec4 vPosition;
out vec4 vPrevPosition;

void main()
{
  // vTexCoord = vec2(gl_InstanceID % 512, gl_InstanceID / 512);
  vTexCoord = texcoord;
  vec4 misc = texture(particles2, vTexCoord);
  vec4 vTarget = texture(particles3, vTexCoord);
  vTemperature = misc.x;
  vAge = misc.y;
  if(uEnergy > 0) {
    vPos = texture(particles0, vTexCoord).xyz;
  }
  else {
    vPos = texture(particles5, vTexCoord).xyz;
  }
  vPosition = modelViewMatrix * vec4(vPos, 1.0);
  vPrevPosition = modelViewMatrix * vec4(texture(particles4, vTexCoord).xyz, 1.0);
}