/****************************************************************************
 Copyright (c) 2018-2019 Xiamen Yaji Software Co., Ltd.

 http://www.cocos2d-x.org

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/
 

const char* CC3D_positionTexture_vert = R"(

attribute vec4 a_position;
attribute vec2 a_texCoord;

varying vec2 TextureCoordOut;

uniform mat4 u_MVPMatrix;

void main(void)
{
    gl_Position = u_MVPMatrix * a_position;
    TextureCoordOut = a_texCoord;
    TextureCoordOut.y = 1.0 - TextureCoordOut.y;
}
)";

const char* CC3D_skinPositionTexture_vert = R"(
attribute vec3 a_position;

attribute vec4 a_blendWeight;
attribute vec4 a_blendIndex;

attribute vec2 a_texCoord;

const int SKINNING_JOINT_COUNT = 60;
// Uniforms
uniform vec4 u_matrixPalette[SKINNING_JOINT_COUNT * 3];
uniform mat4 u_MVPMatrix;

// Varyings
varying vec2 TextureCoordOut;

vec4 getPosition()
{
    float blendWeight = a_blendWeight[0];

    int matrixIndex = int (a_blendIndex[0]) * 3;
    vec4 matrixPalette1 = u_matrixPalette[matrixIndex] * blendWeight;
    vec4 matrixPalette2 = u_matrixPalette[matrixIndex + 1] * blendWeight;
    vec4 matrixPalette3 = u_matrixPalette[matrixIndex + 2] * blendWeight;


    blendWeight = a_blendWeight[1];
    if (blendWeight > 0.0)
    {
        matrixIndex = int(a_blendIndex[1]) * 3;
        matrixPalette1 += u_matrixPalette[matrixIndex] * blendWeight;
        matrixPalette2 += u_matrixPalette[matrixIndex + 1] * blendWeight;
        matrixPalette3 += u_matrixPalette[matrixIndex + 2] * blendWeight;

        blendWeight = a_blendWeight[2];
        if (blendWeight > 0.0)
        {
            matrixIndex = int(a_blendIndex[2]) * 3;
            matrixPalette1 += u_matrixPalette[matrixIndex] * blendWeight;
            matrixPalette2 += u_matrixPalette[matrixIndex + 1] * blendWeight;
            matrixPalette3 += u_matrixPalette[matrixIndex + 2] * blendWeight;

            blendWeight = a_blendWeight[3];
            if (blendWeight > 0.0)
            {
                matrixIndex = int(a_blendIndex[3]) * 3;
                matrixPalette1 += u_matrixPalette[matrixIndex] * blendWeight;
                matrixPalette2 += u_matrixPalette[matrixIndex + 1] * blendWeight;
                matrixPalette3 += u_matrixPalette[matrixIndex + 2] * blendWeight;
            }
        }
    }

    vec4 _skinnedPosition;
    vec4 position = vec4(a_position, 1.0);
    _skinnedPosition.x = dot(position, matrixPalette1);
    _skinnedPosition.y = dot(position, matrixPalette2);
    _skinnedPosition.z = dot(position, matrixPalette3);
    _skinnedPosition.w = position.w;

    return _skinnedPosition;
}

void main()
{
    vec4 position = getPosition();
    gl_Position = u_MVPMatrix * position;

    TextureCoordOut = a_texCoord;
    TextureCoordOut.y = 1.0 - TextureCoordOut.y;
}

)";