overte-HifiExperiments/libraries/render-utils/src/deferred_light_spot.slv

<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  deferred_light_spot.vert
//  vertex shader
//
//  Created by Sam Gateau on 7/8/15.
//  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/Inputs.slh@>

<@include gpu/Transform.slh@>

<$declareStandardTransform()$>

uniform mat4 texcoordMat;
uniform vec4 coneParam;

out vec4 _texCoord0;

void main(void) {
    vec4 coneVertex = inPosition;
    if (coneParam.w != 0.0) {
        if(coneVertex.z >= 0.0) {
            // Evaluate the true position of the spot volume
            vec2 dir =  float(coneVertex.z < 0.5f) * (coneParam.xy
                            +   vec2(coneParam.y, -coneParam.x) * coneParam.z * float(coneVertex.z > 0.0f))
                     +  float(coneVertex.z > 0.5f) * (vec2(1.0, 0.0)
                            +   vec2(0.0, coneParam.z) * float(coneVertex.z < 1.0f));

            coneVertex.xy *= dir.y;
            coneVertex.z = -dir.x;
        } else {
            coneVertex.z = 0.0;
        }
    }

    // standard transform
    TransformCamera cam = getTransformCamera();
    TransformObject obj = getTransformObject();
    <$transformModelToClipPos(cam, obj, coneVertex, gl_Position)$>;

    vec4 projected = gl_Position / gl_Position.w;
    _texCoord0 = vec4(dot(projected, texcoordMat[0]) * gl_Position.w,
        dot(projected, texcoordMat[1]) * gl_Position.w, 0.0, gl_Position.w);
}