/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtOpenGL module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
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** General Public License version 3 as published by the Free Software
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** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
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** information to ensure the GNU General Public License requirements will
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//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//


#ifndef QOPENGL_ENGINE_SHADER_SOURCE_H
#define QOPENGL_ENGINE_SHADER_SOURCE_H

#include "qopenglengineshadermanager_p.h"

QT_BEGIN_NAMESPACE


static const char* const qopenglslMainVertexShader = "\n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
    }\n";

static const char* const qopenglslMainWithTexCoordsVertexShader = "\n\
    attribute highp   vec2      textureCoordArray; \n\
    varying   highp   vec2      textureCoords; \n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
        textureCoords = textureCoordArray; \n\
    }\n";

static const char* const qopenglslMainWithTexCoordsAndOpacityVertexShader = "\n\
    attribute highp   vec2      textureCoordArray; \n\
    attribute lowp    float     opacityArray; \n\
    varying   highp   vec2      textureCoords; \n\
    varying   lowp    float     opacity; \n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
        textureCoords = textureCoordArray; \n\
        opacity = opacityArray; \n\
    }\n";

// NOTE: We let GL do the perspective correction so texture lookups in the fragment
//       shader are also perspective corrected.
static const char* const qopenglslPositionOnlyVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray; \n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    void setPosition(void) \n\
    { \n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position = vec4(transformedPos.xy, 0.0, transformedPos.z); \n\
    }\n";

static const char* const qopenglslComplexGeometryPositionOnlyVertexShader = "\n\
    uniform highp mat3 matrix; \n\
    attribute highp vec2 vertexCoordsArray; \n\
    void setPosition(void) \n\
    { \n\
      gl_Position = vec4(matrix * vec3(vertexCoordsArray, 1), 1);\n\
    } \n";

static const char* const qopenglslUntransformedPositionVertexShader = "\n\
    attribute highp   vec4      vertexCoordsArray; \n\
    void setPosition(void) \n\
    { \n\
        gl_Position = vertexCoordsArray; \n\
    }\n";

// Pattern Brush - This assumes the texture size is 8x8 and thus, the inverted size is 0.125
static const char* const qopenglslPositionWithPatternBrushVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray; \n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    uniform   mediump vec2      halfViewportSize; \n\
    uniform   highp   vec2      invertedTextureSize; \n\
    uniform   highp   mat3      brushTransform; \n\
    varying   highp   vec2      patternTexCoords; \n\
    void setPosition(void) \n\
    { \n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        mediump vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        mediump vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1.0); \n\
        mediump float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        patternTexCoords.xy = (hTexCoords.xy * 0.125) * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithPatternBrushVertexShader
                 = qopenglslPositionWithPatternBrushVertexShader;

static const char* const qopenglslPatternBrushSrcFragmentShader = "\n\
    uniform           sampler2D brushTexture; \n\
    uniform   lowp    vec4      patternColor; \n\
    varying   highp   vec2      patternTexCoords;\n\
    lowp vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture2D(brushTexture, patternTexCoords).r); \n\
    }\n";


// Linear Gradient Brush
static const char* const qopenglslPositionWithLinearGradientBrushVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray; \n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    uniform   mediump vec2      halfViewportSize; \n\
    uniform   highp   vec3      linearData; \n\
    uniform   highp   mat3      brushTransform; \n\
    varying   mediump float     index; \n\
    void setPosition() \n\
    { \n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        mediump vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        mediump vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        mediump float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        index = (dot(linearData.xy, hTexCoords.xy) * linearData.z) * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithLinearGradientBrushVertexShader
                 = qopenglslPositionWithLinearGradientBrushVertexShader;

static const char* const qopenglslLinearGradientBrushSrcFragmentShader = "\n\
    uniform           sampler2D brushTexture; \n\
    varying   mediump float     index; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        mediump vec2 val = vec2(index, 0.5); \n\
        return texture2D(brushTexture, val); \n\
    }\n";


// Conical Gradient Brush
static const char* const qopenglslPositionWithConicalGradientBrushVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray; \n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    uniform   mediump vec2      halfViewportSize; \n\
    uniform   highp   mat3      brushTransform; \n\
    varying   highp   vec2      A; \n\
    void setPosition(void) \n\
    { \n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        mediump vec2  viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        mediump vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        mediump float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        A = hTexCoords.xy * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithConicalGradientBrushVertexShader
                 = qopenglslPositionWithConicalGradientBrushVertexShader;

static const char* const qopenglslConicalGradientBrushSrcFragmentShader = "\n\
    #define INVERSE_2PI 0.1591549430918953358 \n\
    uniform           sampler2D brushTexture; \n\
    uniform   mediump float     angle; \n\
    varying   highp   vec2      A; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        highp float t; \n\
        if (abs(A.y) == abs(A.x)) \n\
            t = (atan(-A.y + 0.002, A.x) + angle) * INVERSE_2PI; \n\
        else \n\
            t = (atan(-A.y, A.x) + angle) * INVERSE_2PI; \n\
        return texture2D(brushTexture, vec2(t - floor(t), 0.5)); \n\
    }\n";


// Radial Gradient Brush
static const char* const qopenglslPositionWithRadialGradientBrushVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray;\n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    uniform   mediump vec2      halfViewportSize; \n\
    uniform   highp   mat3      brushTransform; \n\
    uniform   highp   vec2      fmp; \n\
    uniform   mediump vec3      bradius; \n\
    varying   highp   float     b; \n\
    varying   highp   vec2      A; \n\
    void setPosition(void) \n\
    {\n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        mediump vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        mediump vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        mediump float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        A = hTexCoords.xy * invertedHTexCoordsZ; \n\
        b = bradius.x + 2.0 * dot(A, fmp); \n\
    }\n";

static const char* const qopenglslAffinePositionWithRadialGradientBrushVertexShader
                 = qopenglslPositionWithRadialGradientBrushVertexShader;

static const char* const qopenglslRadialGradientBrushSrcFragmentShader = "\n\
    uniform           sampler2D brushTexture; \n\
    uniform   highp   float     fmp2_m_radius2; \n\
    uniform   highp   float     inverse_2_fmp2_m_radius2; \n\
    uniform   highp   float     sqrfr; \n\
    varying   highp   float     b; \n\
    varying   highp   vec2      A; \n\
    uniform   mediump vec3      bradius; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        highp float c = sqrfr-dot(A, A); \n\
        highp float det = b*b - 4.0*fmp2_m_radius2*c; \n\
        lowp vec4 result = vec4(0.0); \n\
        if (det >= 0.0) { \n\
            highp float detSqrt = sqrt(det); \n\
            highp float w = max((-b - detSqrt) * inverse_2_fmp2_m_radius2, (-b + detSqrt) * inverse_2_fmp2_m_radius2); \n\
            if (bradius.y + w * bradius.z >= 0.0) \n\
                result = texture2D(brushTexture, vec2(w, 0.5)); \n\
        } \n\
        return result; \n\
    }\n";


// Texture Brush
static const char* const qopenglslPositionWithTextureBrushVertexShader = "\n\
    attribute highp   vec2      vertexCoordsArray; \n\
    attribute highp   vec3      pmvMatrix1; \n\
    attribute highp   vec3      pmvMatrix2; \n\
    attribute highp   vec3      pmvMatrix3; \n\
    uniform   mediump vec2      halfViewportSize; \n\
    uniform   highp   vec2      invertedTextureSize; \n\
    uniform   highp   mat3      brushTransform; \n\
    varying   highp   vec2      brushTextureCoords; \n\
    void setPosition(void) \n\
    { \n\
        highp mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        mediump vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        mediump vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        mediump float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        brushTextureCoords.xy = (hTexCoords.xy * invertedTextureSize) * gl_Position.w; \n\
    }\n";

static const char* const qopenglslAffinePositionWithTextureBrushVertexShader
                 = qopenglslPositionWithTextureBrushVertexShader;

static const char* const qopenglslTextureBrushSrcFragmentShader = "\n\
    varying   highp   vec2      brushTextureCoords; \n\
    uniform           sampler2D brushTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return texture2D(brushTexture, brushTextureCoords); \n\
    }\n";

static const char* const qopenglslTextureBrushSrcWithPatternFragmentShader = "\n\
    varying   highp   vec2      brushTextureCoords; \n\
    uniform   lowp    vec4      patternColor; \n\
    uniform           sampler2D brushTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture2D(brushTexture, brushTextureCoords).r); \n\
    }\n";

// Solid Fill Brush
static const char* const qopenglslSolidBrushSrcFragmentShader = "\n\
    uniform   lowp    vec4      fragmentColor; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return fragmentColor; \n\
    }\n";

static const char* const qopenglslImageSrcFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform           sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n"
        "return texture2D(imageTexture, textureCoords); \n"
    "}\n";

static const char* const qopenglslCustomSrcFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform           sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return customShader(imageTexture, textureCoords); \n\
    }\n";

static const char* const qopenglslImageSrcWithPatternFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform   lowp    vec4      patternColor; \n\
    uniform           sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture2D(imageTexture, textureCoords).r); \n\
    }\n";

static const char* const qopenglslNonPremultipliedImageSrcFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform          sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        lowp vec4 sample = texture2D(imageTexture, textureCoords); \n\
        sample.rgb = sample.rgb * sample.a; \n\
        return sample; \n\
    }\n";

static const char* const qopenglslGrayscaleImageSrcFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform          sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return texture2D(imageTexture, textureCoords).rrra; \n\
    }\n";

static const char* const qopenglslAlphaImageSrcFragmentShader = "\n\
    varying   highp   vec2      textureCoords; \n\
    uniform          sampler2D imageTexture; \n\
    lowp vec4 srcPixel() \n\
    { \n\
        return vec4(0, 0, 0, texture2D(imageTexture, textureCoords).r); \n\
    }\n";

static const char* const qopenglslShockingPinkSrcFragmentShader = "\n\
    lowp vec4 srcPixel() \n\
    { \n\
        return vec4(0.98, 0.06, 0.75, 1.0); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_ImageArrays = "\n\
    varying   lowp    float     opacity; \n\
    lowp vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        gl_FragColor = srcPixel() * opacity; \n\
    }\n";

static const char* const qopenglslMainFragmentShader_MO = "\n\
    uniform   lowp    float     globalOpacity; \n\
    lowp vec4 srcPixel(); \n\
    lowp vec4 applyMask(lowp vec4); \n\
    void main() \n\
    { \n\
        gl_FragColor = applyMask(srcPixel()*globalOpacity); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_M = "\n\
    lowp vec4 srcPixel(); \n\
    lowp vec4 applyMask(lowp vec4); \n\
    void main() \n\
    { \n\
        gl_FragColor = applyMask(srcPixel()); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_O = "\n\
    uniform   lowp    float     globalOpacity; \n\
    lowp vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        gl_FragColor = srcPixel()*globalOpacity; \n\
    }\n";

static const char* const qopenglslMainFragmentShader = "\n\
    lowp vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        gl_FragColor = srcPixel(); \n\
    }\n";

static const char* const qopenglslMaskFragmentShader = "\n\
    varying   highp   vec2      textureCoords;\n\
    uniform           sampler2D maskTexture;\n\
    lowp vec4 applyMask(lowp vec4 src) \n\
    {\n\
        lowp vec4 mask = texture2D(maskTexture, textureCoords); \n\
        return src * mask.a; \n\
    }\n";

// For source over with subpixel antialiasing, the final color is calculated per component as follows
// (.a is alpha component, .c is red, green or blue component):
// alpha = src.a * mask.c * opacity
// dest.c = dest.c * (1 - alpha) + src.c * alpha
//
// In the first pass, calculate: dest.c = dest.c * (1 - alpha) with blend funcs: zero, 1 - source color
// In the second pass, calculate: dest.c = dest.c + src.c * alpha with blend funcs: one, one
//
// If source is a solid color (src is constant), only the first pass is needed, with blend funcs: constant, 1 - source color

// For source composition with subpixel antialiasing, the final color is calculated per component as follows:
// alpha = src.a * mask.c * opacity
// dest.c = dest.c * (1 - mask.c) + src.c * alpha
//

static const char* const qopenglslRgbMaskFragmentShaderPass1 = "\n\
    varying   highp   vec2      textureCoords;\n\
    uniform           sampler2D maskTexture;\n\
    lowp vec4 applyMask(lowp vec4 src) \n\
    { \n\
        lowp vec4 mask = texture2D(maskTexture, textureCoords); \n\
        return src.a * mask; \n\
    }\n";

static const char* const qopenglslRgbMaskFragmentShaderPass2 = "\n\
    varying   highp   vec2      textureCoords;\n\
    uniform           sampler2D maskTexture;\n\
    lowp vec4 applyMask(lowp vec4 src) \n\
    { \n\
        lowp vec4 mask = texture2D(maskTexture, textureCoords); \n\
        return src * mask; \n\
    }\n";

static const char* const qopenglslMultiplyCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_multiply) out;\n\
    #endif\n";

static const char* const qopenglslScreenCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_screen) out;\n\
    #endif\n";

static const char* const qopenglslOverlayCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_overlay) out;\n\
    #endif\n";

static const char* const qopenglslDarkenCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_darken) out;\n\
    #endif\n";

static const char* const qopenglslLightenCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_lighten) out;\n\
    #endif\n";

static const char* const qopenglslColorDodgeCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_colordodge) out;\n\
    #endif\n";

static const char* const qopenglslColorBurnCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_colorburn) out;\n\
    #endif\n";

static const char* const qopenglslHardLightCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_hardlight) out;\n\
    #endif\n";

static const char* const qopenglslSoftLightCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_softlight) out;\n\
    #endif\n";

static const char* const qopenglslDifferenceCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_difference) out;\n\
    #endif\n";

static const char* const qopenglslExclusionCompositionModeFragmentShader = "\n\
    #ifdef GL_KHR_blend_equation_advanced\n\
    layout(blend_support_exclusion) out;\n\
    #endif\n";

/*
    Left to implement:
        RgbMaskFragmentShader,
        RgbMaskWithGammaFragmentShader,
*/

/*
    OpenGL 3.2+ Core Profile shaders
    The following shader snippets are copies of the snippets above
    but use the modern GLSL 1.5 keywords. New shaders should make
    a snippet for both profiles and add them appropriately in the
    shader manager.
*/
static const char* const qopenglslMainVertexShader_core =
    "#version 150 core\n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
    }\n";

static const char* const qopenglslMainWithTexCoordsVertexShader_core =
    "#version 150 core\n\
    in      vec2      textureCoordArray; \n\
    out     vec2      textureCoords; \n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
        textureCoords = textureCoordArray; \n\
    }\n";

static const char* const qopenglslMainWithTexCoordsAndOpacityVertexShader_core =
    "#version 150 core\n\
    in      vec2      textureCoordArray; \n\
    in      float     opacityArray; \n\
    out     vec2      textureCoords; \n\
    out     float     opacity; \n\
    void setPosition(); \n\
    void main(void) \n\
    { \n\
        setPosition(); \n\
        textureCoords = textureCoordArray; \n\
        opacity = opacityArray; \n\
    }\n";

// NOTE: We let GL do the perspective correction so texture lookups in the fragment
//       shader are also perspective corrected.
static const char* const qopenglslPositionOnlyVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    void setPosition(void) \n\
    { \n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position = vec4(transformedPos.xy, 0.0, transformedPos.z); \n\
    }\n";

static const char* const qopenglslComplexGeometryPositionOnlyVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    uniform mat3      matrix; \n\
    void setPosition(void) \n\
    { \n\
      gl_Position = vec4(matrix * vec3(vertexCoordsArray, 1), 1);\n\
    } \n";

static const char* const qopenglslUntransformedPositionVertexShader_core = "\n\
    in      vec4      vertexCoordsArray; \n\
    void setPosition(void) \n\
    { \n\
        gl_Position = vertexCoordsArray; \n\
    }\n";

// Pattern Brush - This assumes the texture size is 8x8 and thus, the inverted size is 0.125
static const char* const qopenglslPositionWithPatternBrushVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    out     vec2      patternTexCoords; \n\
    uniform vec2      halfViewportSize; \n\
    uniform vec2      invertedTextureSize; \n\
    uniform mat3      brushTransform; \n\
    void setPosition(void) \n\
    { \n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1.0); \n\
        float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        patternTexCoords.xy = (hTexCoords.xy * 0.125) * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithPatternBrushVertexShader_core
                 = qopenglslPositionWithPatternBrushVertexShader_core;

static const char* const qopenglslPatternBrushSrcFragmentShader_core = "\n\
    in      vec2      patternTexCoords;\n\
    uniform sampler2D brushTexture; \n\
    uniform vec4      patternColor; \n\
    vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture(brushTexture, patternTexCoords).r); \n\
    }\n";


// Linear Gradient Brush
static const char* const qopenglslPositionWithLinearGradientBrushVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    out     float     index; \n\
    uniform vec2      halfViewportSize; \n\
    uniform vec3      linearData; \n\
    uniform mat3      brushTransform; \n\
    void setPosition() \n\
    { \n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        index = (dot(linearData.xy, hTexCoords.xy) * linearData.z) * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithLinearGradientBrushVertexShader_core
                 = qopenglslPositionWithLinearGradientBrushVertexShader_core;

static const char* const qopenglslLinearGradientBrushSrcFragmentShader_core = "\n\
    uniform sampler2D brushTexture; \n\
    in      float     index; \n\
    vec4 srcPixel() \n\
    { \n\
        vec2 val = vec2(index, 0.5); \n\
        return texture(brushTexture, val); \n\
    }\n";


// Conical Gradient Brush
static const char* const qopenglslPositionWithConicalGradientBrushVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    out     vec2      A; \n\
    uniform vec2      halfViewportSize; \n\
    uniform mat3      brushTransform; \n\
    void setPosition(void) \n\
    { \n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        vec2  viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        A = hTexCoords.xy * invertedHTexCoordsZ; \n\
    }\n";

static const char* const qopenglslAffinePositionWithConicalGradientBrushVertexShader_core
                 = qopenglslPositionWithConicalGradientBrushVertexShader_core;

static const char* const qopenglslConicalGradientBrushSrcFragmentShader_core = "\n\
    #define INVERSE_2PI 0.1591549430918953358 \n\
    in      vec2      A; \n\
    uniform sampler2D brushTexture; \n\
    uniform float     angle; \n\
    vec4 srcPixel() \n\
    { \n\
        float t; \n\
        if (abs(A.y) == abs(A.x)) \n\
            t = (atan(-A.y + 0.002, A.x) + angle) * INVERSE_2PI; \n\
        else \n\
            t = (atan(-A.y, A.x) + angle) * INVERSE_2PI; \n\
        return texture(brushTexture, vec2(t - floor(t), 0.5)); \n\
    }\n";


// Radial Gradient Brush
static const char* const qopenglslPositionWithRadialGradientBrushVertexShader_core = "\n\
    in      vec2      vertexCoordsArray;\n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    out     float     b; \n\
    out     vec2      A; \n\
    uniform vec2      halfViewportSize; \n\
    uniform mat3      brushTransform; \n\
    uniform vec2      fmp; \n\
    uniform vec3      bradius; \n\
    void setPosition(void) \n\
    {\n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        A = hTexCoords.xy * invertedHTexCoordsZ; \n\
        b = bradius.x + 2.0 * dot(A, fmp); \n\
    }\n";

static const char* const qopenglslAffinePositionWithRadialGradientBrushVertexShader_core
                 = qopenglslPositionWithRadialGradientBrushVertexShader_core;

static const char* const qopenglslRadialGradientBrushSrcFragmentShader_core = "\n\
    in      float     b; \n\
    in      vec2      A; \n\
    uniform sampler2D brushTexture; \n\
    uniform float     fmp2_m_radius2; \n\
    uniform float     inverse_2_fmp2_m_radius2; \n\
    uniform float     sqrfr; \n\
    uniform vec3      bradius; \n\
    \n\
    vec4 srcPixel() \n\
    { \n\
        float c = sqrfr-dot(A, A); \n\
        float det = b*b - 4.0*fmp2_m_radius2*c; \n\
        vec4 result = vec4(0.0); \n\
        if (det >= 0.0) { \n\
            float detSqrt = sqrt(det); \n\
            float w = max((-b - detSqrt) * inverse_2_fmp2_m_radius2, (-b + detSqrt) * inverse_2_fmp2_m_radius2); \n\
            if (bradius.y + w * bradius.z >= 0.0) \n\
                result = texture(brushTexture, vec2(w, 0.5)); \n\
        } \n\
        return result; \n\
    }\n";


// Texture Brush
static const char* const qopenglslPositionWithTextureBrushVertexShader_core = "\n\
    in      vec2      vertexCoordsArray; \n\
    in      vec3      pmvMatrix1; \n\
    in      vec3      pmvMatrix2; \n\
    in      vec3      pmvMatrix3; \n\
    out     vec2      brushTextureCoords; \n\
    uniform vec2      halfViewportSize; \n\
    uniform vec2      invertedTextureSize; \n\
    uniform mat3      brushTransform; \n\
    \n\
    void setPosition(void) \n\
    { \n\
        mat3 pmvMatrix = mat3(pmvMatrix1, pmvMatrix2, pmvMatrix3); \n\
        vec3 transformedPos = pmvMatrix * vec3(vertexCoordsArray.xy, 1.0); \n\
        gl_Position.xy = transformedPos.xy / transformedPos.z; \n\
        vec2 viewportCoords = (gl_Position.xy + 1.0) * halfViewportSize; \n\
        vec3 hTexCoords = brushTransform * vec3(viewportCoords, 1); \n\
        float invertedHTexCoordsZ = 1.0 / hTexCoords.z; \n\
        gl_Position = vec4(gl_Position.xy * invertedHTexCoordsZ, 0.0, invertedHTexCoordsZ); \n\
        brushTextureCoords.xy = (hTexCoords.xy * invertedTextureSize) * gl_Position.w; \n\
    }\n";

static const char* const qopenglslAffinePositionWithTextureBrushVertexShader_core
                 = qopenglslPositionWithTextureBrushVertexShader_core;

static const char* const qopenglslTextureBrushSrcFragmentShader_core = "\n\
    in      vec2      brushTextureCoords; \n\
    uniform sampler2D brushTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return texture(brushTexture, brushTextureCoords); \n\
    }\n";

static const char* const qopenglslTextureBrushSrcWithPatternFragmentShader_core = "\n\
    in      vec2      brushTextureCoords; \n\
    uniform vec4      patternColor; \n\
    uniform sampler2D brushTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture(brushTexture, brushTextureCoords).r); \n\
    }\n";

// Solid Fill Brush
static const char* const qopenglslSolidBrushSrcFragmentShader_core = "\n\
    uniform vec4      fragmentColor; \n\
    vec4 srcPixel() \n\
    { \n\
        return fragmentColor; \n\
    }\n";

static const char* const qopenglslImageSrcFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return texture(imageTexture, textureCoords); \n\
    }\n";

static const char* const qopenglslCustomSrcFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return customShader(imageTexture, textureCoords); \n\
    }\n";

static const char* const qopenglslImageSrcWithPatternFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform vec4      patternColor; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return patternColor * (1.0 - texture(imageTexture, textureCoords).r); \n\
    }\n";

static const char* const qopenglslNonPremultipliedImageSrcFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        vec4 sample = texture(imageTexture, textureCoords); \n\
        sample.rgb = sample.rgb * sample.a; \n\
        return sample; \n\
    }\n";

static const char* const qopenglslGrayscaleImageSrcFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return texture(imageTexture, textureCoords).rrra; \n\
    }\n";

static const char* const qopenglslAlphaImageSrcFragmentShader_core = "\n\
    in      vec2      textureCoords; \n\
    uniform sampler2D imageTexture; \n\
    vec4 srcPixel() \n\
    { \n\
        return vec4(0, 0, 0, texture(imageTexture, textureCoords).r); \n\
    }\n";

static const char* const qopenglslShockingPinkSrcFragmentShader_core = "\n\
    vec4 srcPixel() \n\
    { \n\
        return vec4(0.98, 0.06, 0.75, 1.0); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_ImageArrays_core =
    "#version 150 core\n\
    in      float     opacity; \n\
    out     vec4      fragColor; \n\
    vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        fragColor = srcPixel() * opacity; \n\
    }\n";

static const char* const qopenglslMainFragmentShader_MO_core =
    "#version 150 core\n\
    out     vec4      fragColor; \n\
    uniform float     globalOpacity; \n\
    vec4 srcPixel(); \n\
    vec4 applyMask(vec4); \n\
    void main() \n\
    { \n\
        fragColor = applyMask(srcPixel()*globalOpacity); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_M_core =
    "#version 150 core\n\
    out     vec4      fragColor; \n\
    vec4 srcPixel(); \n\
    vec4 applyMask(vec4); \n\
    void main() \n\
    { \n\
        fragColor = applyMask(srcPixel()); \n\
    }\n";

static const char* const qopenglslMainFragmentShader_O_core =
    "#version 150 core\n\
    out     vec4      fragColor; \n\
    uniform float     globalOpacity; \n\
    vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        fragColor = srcPixel()*globalOpacity; \n\
    }\n";

static const char* const qopenglslMainFragmentShader_core =
    "#version 150 core\n\
    out     vec4      fragColor; \n\
    vec4 srcPixel(); \n\
    void main() \n\
    { \n\
        fragColor = srcPixel(); \n\
    }\n";

static const char* const qopenglslMaskFragmentShader_core = "\n\
    in      vec2      textureCoords;\n\
    uniform sampler2D maskTexture;\n\
    vec4 applyMask(vec4 src) \n\
    {\n\
        vec4 mask = texture(maskTexture, textureCoords); \n\
        return src * mask.r; \n\
    }\n";

// For source over with subpixel antialiasing, the final color is calculated per component as follows
// (.a is alpha component, .c is red, green or blue component):
// alpha = src.a * mask.c * opacity
// dest.c = dest.c * (1 - alpha) + src.c * alpha
//
// In the first pass, calculate: dest.c = dest.c * (1 - alpha) with blend funcs: zero, 1 - source color
// In the second pass, calculate: dest.c = dest.c + src.c * alpha with blend funcs: one, one
//
// If source is a solid color (src is constant), only the first pass is needed, with blend funcs: constant, 1 - source color

// For source composition with subpixel antialiasing, the final color is calculated per component as follows:
// alpha = src.a * mask.c * opacity
// dest.c = dest.c * (1 - mask.c) + src.c * alpha
//

static const char* const qopenglslRgbMaskFragmentShaderPass1_core = "\n\
    in      vec2      textureCoords;\n\
    uniform sampler2D maskTexture;\n\
    vec4 applyMask(vec4 src) \n\
    { \n\
        vec4 mask = texture(maskTexture, textureCoords); \n\
        return src.a * mask; \n\
    }\n";

static const char* const qopenglslRgbMaskFragmentShaderPass2_core = "\n\
    in      vec2      textureCoords;\n\
    uniform sampler2D maskTexture;\n\
    vec4 applyMask(vec4 src) \n\
    { \n\
        vec4 mask = texture(maskTexture, textureCoords); \n\
        return src * mask; \n\
    }\n";

/*
    Left to implement:
        RgbMaskFragmentShader_core,
        RgbMaskWithGammaFragmentShader_core,
*/

QT_END_NAMESPACE

#endif // GLGC_SHADER_SOURCE_H
