#ifdef COMPILEVS

// Silence WARNING: Shader ... does not use the define NOUV
#ifdef NOUV
#endif

// Silence GLSL 150 deprecation warnings
#ifdef GL3
#define attribute in
#define varying out
#endif

attribute vec4 iPos;
attribute vec3 iNormal;
attribute vec4 iColor;
attribute vec2 iTexCoord;
attribute vec2 iTexCoord1;
attribute vec4 iTangent;
attribute vec4 iBlendWeights;
attribute vec4 iBlendIndices;
attribute vec3 iCubeTexCoord;
attribute vec4 iCubeTexCoord1;
#ifdef INSTANCED
    attribute vec4 iTexCoord4;
    attribute vec4 iTexCoord5;
    attribute vec4 iTexCoord6;
#endif
attribute float iObjectIndex;

#ifdef SKINNED
mat4 GetSkinMatrix(vec4 blendWeights, vec4 blendIndices)
{
    ivec4 idx = ivec4(blendIndices) * 3;
    const vec4 lastColumn = vec4(0.0, 0.0, 0.0, 1.0);
    return mat4(cSkinMatrices[idx.x], cSkinMatrices[idx.x + 1], cSkinMatrices[idx.x + 2], lastColumn) * blendWeights.x +
        mat4(cSkinMatrices[idx.y], cSkinMatrices[idx.y + 1], cSkinMatrices[idx.y + 2], lastColumn) * blendWeights.y +
        mat4(cSkinMatrices[idx.z], cSkinMatrices[idx.z + 1], cSkinMatrices[idx.z + 2], lastColumn) * blendWeights.z +
        mat4(cSkinMatrices[idx.w], cSkinMatrices[idx.w + 1], cSkinMatrices[idx.w + 2], lastColumn) * blendWeights.w;
}
#endif

#ifdef INSTANCED
mat4 GetInstanceMatrix()
{
    const vec4 lastColumn = vec4(0.0, 0.0, 0.0, 1.0);
    return mat4(iTexCoord4, iTexCoord5, iTexCoord6, lastColumn);
}
#endif

mat3 GetNormalMatrix(mat4 modelMatrix)
{
    return mat3(modelMatrix[0].xyz, modelMatrix[1].xyz, modelMatrix[2].xyz);
}

vec2 GetTexCoord(vec2 texCoord)
{
    return vec2(dot(texCoord, cUOffset.xy) + cUOffset.w, dot(texCoord, cVOffset.xy) + cVOffset.w);
}

vec4 GetClipPos(vec3 worldPos)
{
    vec4 ret = vec4(worldPos, 1.0) * cViewProj;
    // While getting the clip coordinate, also automatically set gl_ClipVertex for user clip planes
    #if !defined(GL_ES) && !defined(GL3)
        gl_ClipVertex = ret;
    #elif defined(GL3)
        gl_ClipDistance[0] = dot(cClipPlane, ret);
    #endif
    return ret;
}

float GetZonePos(vec3 worldPos)
{
    return clamp((vec4(worldPos, 1.0) * cZone).z, 0.0, 1.0);
}

float GetDepth(vec4 clipPos)
{
    return dot(clipPos.zw, cDepthMode.zw);
}

#ifdef BILLBOARD
vec3 GetBillboardPos(vec4 iPos, vec2 iSize, mat4 modelMatrix)
{
    return (iPos * modelMatrix).xyz + vec3(iSize.x, iSize.y, 0.0) * cBillboardRot;
}

vec3 GetBillboardNormal()
{
    return vec3(-cBillboardRot[0][2], -cBillboardRot[1][2], -cBillboardRot[2][2]);
}
#endif

#ifdef DIRBILLBOARD
mat3 GetFaceCameraRotation(vec3 position, vec3 direction)
{
    vec3 cameraDir = normalize(position - cCameraPos);
    vec3 front = normalize(direction);
    vec3 right = normalize(cross(front, cameraDir));
    vec3 up = normalize(cross(front, right));

    return mat3(
        right.x, up.x, front.x,
        right.y, up.y, front.y,
        right.z, up.z, front.z
    );
}

vec3 GetBillboardPos(vec4 iPos, vec3 iDirection, mat4 modelMatrix)
{
    vec3 worldPos = (iPos * modelMatrix).xyz;
    return worldPos + vec3(iTexCoord1.x, 0.0, iTexCoord1.y) * GetFaceCameraRotation(worldPos, iDirection);
}

vec3 GetBillboardNormal(vec4 iPos, vec3 iDirection, mat4 modelMatrix)
{
    vec3 worldPos = (iPos * modelMatrix).xyz;
    return vec3(0.0, 1.0, 0.0) * GetFaceCameraRotation(worldPos, iDirection);
}
#endif

#ifdef TRAILFACECAM
vec3 GetTrailPos(vec4 iPos, vec3 iFront, float iScale, mat4 modelMatrix)
{
    vec3 up = normalize(cCameraPos - iPos.xyz);
    vec3 right = normalize(cross(iFront, up));
    return (vec4((iPos.xyz + right * iScale), 1.0) * modelMatrix).xyz;
}

vec3 GetTrailNormal(vec4 iPos)
{
    return normalize(cCameraPos - iPos.xyz);
}
#endif

#ifdef TRAILBONE
vec3 GetTrailPos(vec4 iPos, vec3 iParentPos, float iScale, mat4 modelMatrix)
{
    vec3 right = iParentPos - iPos.xyz;
    return (vec4((iPos.xyz + right * iScale), 1.0) * modelMatrix).xyz;
}

vec3 GetTrailNormal(vec4 iPos, vec3 iParentPos, vec3 iForward)
{
    vec3 left = normalize(iPos.xyz - iParentPos);
    vec3 up = normalize(cross(normalize(iForward), left));
    return up;
}
#endif

#if defined(SKINNED)
    #define iModelMatrix GetSkinMatrix(iBlendWeights, iBlendIndices)
#elif defined(INSTANCED)
    #define iModelMatrix GetInstanceMatrix()
#else
    #define iModelMatrix cModel
#endif

vec3 GetWorldPos(mat4 modelMatrix)
{
    #if defined(BILLBOARD)
        return GetBillboardPos(iPos, iTexCoord1, modelMatrix);
    #elif defined(DIRBILLBOARD)
        return GetBillboardPos(iPos, iNormal, modelMatrix);
    #elif defined(TRAILFACECAM)
        return GetTrailPos(iPos, iTangent.xyz, iTangent.w, modelMatrix);
    #elif defined(TRAILBONE)
        return GetTrailPos(iPos, iTangent.xyz, iTangent.w, modelMatrix);
    #else
        return (iPos * modelMatrix).xyz;
    #endif
}

vec3 GetWorldNormal(mat4 modelMatrix)
{
    #if defined(BILLBOARD)
        return GetBillboardNormal();
    #elif defined(DIRBILLBOARD)
        return GetBillboardNormal(iPos, iNormal, modelMatrix);
    #elif defined(TRAILFACECAM)
        return GetTrailNormal(iPos);
    #elif defined(TRAILBONE)
        return GetTrailNormal(iPos, iTangent.xyz, iNormal);
    #else
        return normalize(iNormal * GetNormalMatrix(modelMatrix));
    #endif
}

vec4 GetWorldTangent(mat4 modelMatrix)
{
    #if defined(BILLBOARD)
        return vec4(normalize(vec3(1.0, 0.0, 0.0) * cBillboardRot), 1.0);
    #elif defined(DIRBILLBOARD)
        return vec4(normalize(vec3(1.0, 0.0, 0.0) * GetNormalMatrix(modelMatrix)), 1.0);
    #else
        return vec4(normalize(iTangent.xyz * GetNormalMatrix(modelMatrix)), iTangent.w);
    #endif
}

#else

// Silence GLSL 150 deprecation warnings
#ifdef GL3
#define varying in

#ifndef MRT_COUNT

#if defined(DEFERRED)
#define MRT_COUNT 4
#elif defined(PREPASS)
#define MRT_COUNT 2
#else
#define MRT_COUNT 1
#endif

#endif

out vec4 fragData[MRT_COUNT];


#define gl_FragColor fragData[0]
#define gl_FragData fragData
#endif

#endif
