<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  lightClusters_drawClusterContent.slv
//  Vertex shader
//
//  Created by Sam Gateau on 9/8/2016
//  Copyright 2015 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

<@include gpu/Transform.slh@>
<$declareStandardTransform()$>

<@include LightClusterGrid.slh@>

<@include gpu/Color.slh@>
<$declareColorWheel()$>


out vec4 varColor;


void main(void) {
    const vec4 UNIT_BOX[8] = vec4[8](
        vec4(0.0, 0.0, 0.0, 1.0),
        vec4(1.0, 0.0, 0.0, 1.0),
        vec4(0.0, 1.0, 0.0, 1.0),
        vec4(1.0, 1.0, 0.0, 1.0),
        vec4(0.0, 0.0, 1.0, 1.0),
        vec4(1.0, 0.0, 1.0, 1.0),
        vec4(0.0, 1.0, 1.0, 1.0),
        vec4(1.0, 1.0, 1.0, 1.0)
    );
    const int UNIT_BOX_LINE_INDICES[24] = int[24](
        0, 1,
        1, 3,
        3, 2,
        2, 0,
        4, 5,
        5, 7,
        7, 6,
        6, 4,
        2, 6,
        3, 7,
        0, 4,
        1, 5
    );
    vec4 pos = UNIT_BOX[UNIT_BOX_LINE_INDICES[gl_VertexID]];

 
    ivec3 cluster = clusterGrid_getCluster(gpu_InstanceID);
    int numLights = cluster.x + cluster.y;

    float numLightsScale = clamp(numLights * 0.1, 0.0, 1.0);

    ivec3 clusterPos = frustumGrid_indexToCluster(gpu_InstanceID);

    float boxScale = 0.99;
    vec3 eyePos = frustumGrid_clusterPosToEye(clusterPos, vec3((1.0 - boxScale) * 0.5 + (1.0 - numLightsScale) * boxScale  * 0.5) + numLightsScale * boxScale * pos.xyz);
    vec4 worldPos = frustumGrid_eyeToWorld(vec4(eyePos.xyz, 1.0));


    // standard transform
    TransformCamera cam = getTransformCamera();
    <$transformWorldToClipPos(cam, worldPos, gl_Position)$>

        varColor = vec4(colorWheel(fract(float(gpu_InstanceID) / float(frustumGrid_numClusters()))), (numLights >0 ? 0.9 : 0.1));
}