axmol/tests/cpp-tests/Source/ShaderTest/ShaderTest.cpp

/****************************************************************************
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.

 https://axmolengine.github.io/

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#include "ShaderTest.h"
#include "../testResource.h"
#include "axmol.h"
#include "renderer/Shaders.h"
#include "renderer/backend/Device.h"

USING_NS_AX;
USING_NS_AX_EXT;

#define SET_UNIFORM(ps, name, value)                          \
    do                                                        \
    {                                                         \
        decltype(value) __v = value;                          \
        auto __loc          = (ps)->getUniformLocation(name); \
        (ps)->setUniform(__loc, &__v, sizeof(__v));           \
    } while (false)

#define SET_TEXTURE(ps, name, idx, value)            \
    do                                               \
    {                                                \
        auto* __v  = value;                          \
        auto __loc = (ps)->getUniformLocation(name); \
        (ps)->setTexture(__loc, idx, __v);           \
    } while (false)

ShaderTests::ShaderTests()
{
    ADD_TEST_CASE(ShaderLensFlare);
    ADD_TEST_CASE(ShaderMandelbrot);
    ADD_TEST_CASE(ShaderJulia);
    ADD_TEST_CASE(ShaderHeart);
    ADD_TEST_CASE(ShaderFlower);
    ADD_TEST_CASE(ShaderPlasma);
    ADD_TEST_CASE(ShaderBlur);
    ADD_TEST_CASE(ShaderRetroEffect);
    ADD_TEST_CASE(ShaderMonjori);
    ADD_TEST_CASE(ShaderGlow);
    ADD_TEST_CASE(ShaderMultiTexture);
}

///---------------------------------------
//
// ShaderNode
//
///---------------------------------------
enum
{
    SIZE_X = 256,
    SIZE_Y = 256,
};

ShaderNode::ShaderNode() : _center(Vec2(0.0f, 0.0f)), _resolution(Vec2(0.0f, 0.0f)), _time(0.0f) {}

ShaderNode::~ShaderNode() {}

ShaderNode* ShaderNode::shaderNodeWithVertex(std::string_view vert, std::string_view frag)
{
    auto node = new ShaderNode();
    node->initWithVertex(vert, frag);
    node->autorelease();

    return node;
}

bool ShaderNode::initWithVertex(std::string_view vert, std::string_view frag)
{
    _vertFileName = vert;
    _fragFileName = frag;

    loadShaderVertex(vert, frag);

    _time       = 0;
    _resolution = Vec2(SIZE_X, SIZE_Y);

    scheduleUpdate();

    setContentSize(Size(SIZE_X, SIZE_Y));
    setAnchorPoint(Vec2(0.5f, 0.5f));

    // init custom command
    auto attrPosLoc = _programState->getAttributeLocation("a_position");
    _programState->setVertexAttrib("a_position", attrPosLoc, backend::VertexFormat::FLOAT2, 0, false);

    float w = SIZE_X, h = SIZE_Y;
    Vec2 vertices[6] = {Vec2(0.0f, 0.0f), Vec2(w, 0.0f), Vec2(w, h), Vec2(0.0f, 0.0f), Vec2(0.0f, h), Vec2(w, h)};
    _programState->setVertexStride(sizeof(Vec2));

    /*
     * TODO: the Y-coordinate of subclasses are flipped in metal
     *
     * keywords: AX_USE_METAL , AX_USE_GL
     */

    _customCommand.createVertexBuffer(sizeof(Vec2), 6, CustomCommand::BufferUsage::STATIC);
    _customCommand.updateVertexBuffer(vertices, sizeof(vertices));

    _customCommand.setDrawType(CustomCommand::DrawType::ARRAY);

    return true;
}

void ShaderNode::loadShaderVertex(std::string_view vert, std::string_view frag)
{
    auto fileUtiles = FileUtils::getInstance();

    // frag
    auto fragmentFilePath = fileUtiles->fullPathForFilename(frag);
    auto fragSource       = fileUtiles->getStringFromFile(fragmentFilePath);

    // vert
    std::string vertSource;
    if (vert.empty())
    {
        vertSource = position_vert;
    }
    else
    {
        std::string vertexFilePath = fileUtiles->fullPathForFilename(vert);
        vertSource                 = fileUtiles->getStringFromFile(vertexFilePath);
    }
    auto program      = ProgramManager::newProgram(vertSource, fragSource, VertexLayoutHelper::setupSprite);
    auto programState = new backend::ProgramState(program);
    setProgramState(programState);
    AX_SAFE_RELEASE(programState);
    AX_SAFE_RELEASE(program);
}

void ShaderNode::update(float dt)
{
    _time += dt;
}

void ShaderNode::setPosition(const Vec2& newPosition)
{
    Node::setPosition(newPosition);
    auto position     = getPosition();
    auto frameSize    = Director::getInstance()->getOpenGLView()->getFrameSize();
    auto visibleSize  = Director::getInstance()->getVisibleSize();
    auto retinaFactor = Director::getInstance()->getOpenGLView()->getRetinaFactor();
    _center           = Vec2(position.x * frameSize.width / visibleSize.width * retinaFactor,
                             position.y * frameSize.height / visibleSize.height * retinaFactor);
}

void ShaderNode::draw(Renderer* renderer, const Mat4& transform, uint32_t flags)
{
    _customCommand.init(_globalZOrder, transform, flags);

    _programState->setUniform(_locResolution, &_resolution, sizeof(_resolution));
    _programState->setUniform(_locCenter, &_center, sizeof(_center));

    auto projectionMatrix = Director::getInstance()->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
    auto finalMatrix      = projectionMatrix * transform;

    _programState->setUniform(_locMVP, finalMatrix.m, sizeof(finalMatrix.m));

    float time = Director::getInstance()->getTotalFrames() * Director::getInstance()->getAnimationInterval();
    Vec4 uTime(time / 10.0f, time, time * 2.0f, time * 4.0f);
    Vec4 sinTime(time / 8.0f, time / 4.0f, time / 2.0f, sinf(time));
    Vec4 cosTime(time / 8.0f, time / 4.0f, time / 2.0f, cosf(time));

    _programState->setUniform(_locTime, &uTime, sizeof(uTime));
    _programState->setUniform(_locSinTime, &sinTime, sizeof(sinTime));
    _programState->setUniform(_locCosTime, &cosTime, sizeof(cosTime));

    renderer->addCommand(&_customCommand);
    AX_INCREMENT_GL_DRAWN_BATCHES_AND_VERTICES(1, 6);
}

void ShaderNode::updateUniforms()
{
    if (_programState == nullptr)
        return;

    _locResolution = _programState->getUniformLocation("resolution");
    _locCenter     = _programState->getUniformLocation("center");
    _locMVP        = _programState->getUniformLocation("u_MVPMatrix");
    _locTime       = _programState->getUniformLocation("u_Time");
    _locSinTime    = _programState->getUniformLocation("u_SinTime");
    _locCosTime    = _programState->getUniformLocation("u_CosTime");
    _locScreenSize = _programState->getUniformLocation("u_screenSize");

    const Vec2& frameSize   = Director::getInstance()->getOpenGLView()->getFrameSize();
    float retinaFactor      = Director::getInstance()->getOpenGLView()->getRetinaFactor();
    auto screenSizeInPixels = frameSize * retinaFactor;
    _programState->setUniform(_locScreenSize, &screenSizeInPixels, sizeof(screenSizeInPixels));
}

/// ShaderMonjori

ShaderMonjori::ShaderMonjori() {}

bool ShaderMonjori::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Monjori.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);

        return true;
    }

    return false;
}

std::string ShaderMonjori::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderMonjori::subtitle() const
{
    return "Monjori plane deformations";
}

/// ShaderMandelbrot
ShaderMandelbrot::ShaderMandelbrot() {}

bool ShaderMandelbrot::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Mandelbrot.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);
        return true;
    }

    return false;
}

std::string ShaderMandelbrot::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderMandelbrot::subtitle() const
{
    return "Mandelbrot shader with Zoom";
}

/// ShaderJulia
ShaderJulia::ShaderJulia() {}

bool ShaderJulia::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Julia.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);
        return true;
    }

    return false;
}

std::string ShaderJulia::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderJulia::subtitle() const
{
    return "Julia shader";
}

/// ShaderHeart
ShaderHeart::ShaderHeart() {}

bool ShaderHeart::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Heart.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);

        return true;
    }

    return false;
}

std::string ShaderHeart::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderHeart::subtitle() const
{
    return "Heart";
}

/// ShaderFlower
ShaderFlower::ShaderFlower() {}

bool ShaderFlower::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Flower.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);

        return true;
    }

    return false;
}

std::string ShaderFlower::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderFlower::subtitle() const
{
    return "Flower";
}

/// ShaderPlasma
ShaderPlasma::ShaderPlasma() {}

bool ShaderPlasma::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/example_Plasma.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(sn);

        return true;
    }

    return false;
}

std::string ShaderPlasma::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderPlasma::subtitle() const
{
    return "Plasma";
}

// ShaderBlur

class SpriteBlur : public Sprite
{
public:
    ~SpriteBlur();
    bool initWithTexture(Texture2D* texture, const Rect& rect);
    void initProgram();

    static SpriteBlur* create(const char* pszFileName);
    void setBlurRadius(float radius);
    void setBlurSampleNum(float num);

protected:
    float _blurRadius;
    float _blurSampleNum;
};

SpriteBlur::~SpriteBlur() {}

SpriteBlur* SpriteBlur::create(const char* pszFileName)
{
    SpriteBlur* pRet = new SpriteBlur();
    bool result      = pRet->initWithFile("");
    ax::log("Test call Sprite::initWithFile with bad file name result is : %s", result ? "true" : "false");

    if (pRet->initWithFile(pszFileName))
    {
        pRet->autorelease();
    }
    else
    {
        AX_SAFE_DELETE(pRet);
    }

    return pRet;
}

bool SpriteBlur::initWithTexture(Texture2D* texture, const Rect& rect)
{
    _blurRadius = 0;
    if (Sprite::initWithTexture(texture, rect))
    {
#if AX_ENABLE_CACHE_TEXTURE_DATA
        auto listener =
            EventListenerCustom::create(EVENT_RENDERER_RECREATED, [this](EventCustom* event) { initProgram(); });

        _eventDispatcher->addEventListenerWithSceneGraphPriority(listener, this);
#endif

        initProgram();

        return true;
    }

    return false;
}

void SpriteBlur::initProgram()
{
    std::string fragSource = FileUtils::getInstance()->getStringFromFile(
        FileUtils::getInstance()->fullPathForFilename("Shaders/example_Blur.fsh"));

    auto program      = ProgramManager::newProgram(positionTextureColor_vert, fragSource, VertexLayoutHelper::setupSprite);
    auto programState = new backend::ProgramState(program);
    setProgramState(programState);
    AX_SAFE_RELEASE(programState);
    AX_SAFE_RELEASE(program);

    auto size = getTexture()->getContentSizeInPixels();

    SET_UNIFORM(_programState, "resolution", size);
    SET_UNIFORM(_programState, "blurRadius", _blurRadius);
    SET_UNIFORM(_programState, "sampleNum", 7.0f);
    SET_UNIFORM(_programState, "u_PMatrix",
                Director::getInstance()->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION));
}

void SpriteBlur::setBlurRadius(float radius)
{
    _blurRadius = radius;
    SET_UNIFORM(_programState, "blurRadius", _blurRadius);
}

void SpriteBlur::setBlurSampleNum(float num)
{
    _blurSampleNum = num;
    SET_UNIFORM(_programState, "sampleNum", _blurSampleNum);
}

// ShaderBlur

ShaderBlur::ShaderBlur() {}

std::string ShaderBlur::title() const
{
    return "Shader: Frag shader";
}

std::string ShaderBlur::subtitle() const
{
    return "Gaussian blur";
}

void ShaderBlur::createSliderCtls()
{
    auto screenSize = Director::getInstance()->getWinSize();

    {
        ControlSlider* slider = ControlSlider::create("extensions/sliderTrack.png", "extensions/sliderProgress.png",
                                                      "extensions/sliderThumb.png");
        slider->setAnchorPoint(Vec2(0.5f, 1.0f));
        slider->setMinimumValue(0.0f);
        slider->setMaximumValue(25.0f);
        slider->setScale(0.6f);
        slider->setPosition(Vec2(screenSize.width / 4.0f, screenSize.height / 3.0f + 24.0f));
        slider->addTargetWithActionForControlEvents(this, cccontrol_selector(ShaderBlur::onRadiusChanged),
                                                    Control::EventType::VALUE_CHANGED);
        slider->setValue(2.0f);
        addChild(slider);
        _sliderRadiusCtl = slider;

        auto label = Label::createWithTTF("Blur Radius", "fonts/arial.ttf", 12.0f);
        addChild(label);
        label->setPosition(Vec2(screenSize.width / 4.0f, screenSize.height / 3.0f));
    }

    {
        ControlSlider* slider = ControlSlider::create("extensions/sliderTrack.png", "extensions/sliderProgress.png",
                                                      "extensions/sliderThumb.png");
        slider->setAnchorPoint(Vec2(0.5f, 1.0f));
        slider->setMinimumValue(0.0f);
        slider->setMaximumValue(11.0f);
        slider->setScale(0.6f);
        slider->setPosition(Vec2(screenSize.width / 4.0f, screenSize.height / 3.0f - 10.0f));
        slider->addTargetWithActionForControlEvents(this, cccontrol_selector(ShaderBlur::onSampleNumChanged),
                                                    Control::EventType::VALUE_CHANGED);
        slider->setValue(7.0f);
        addChild(slider);
        _sliderNumCtrl = slider;

        auto label = Label::createWithTTF("Blur Sample Num", "fonts/arial.ttf", 12.0f);
        addChild(label);
        label->setPosition(Vec2(screenSize.width / 4.0f, screenSize.height / 3.0f - 34.0f));
    }
}

bool ShaderBlur::init()
{
    if (ShaderTestDemo::init())
    {
        _blurSprite = SpriteBlur::create("Images/grossini.png");
        auto sprite = Sprite::create("Images/grossini.png");
        auto s      = Director::getInstance()->getWinSize();
        _blurSprite->setPosition(Vec2(s.width / 3, s.height / 2 + 30.0f));
        sprite->setPosition(Vec2(2 * s.width / 3, s.height / 2 + 30.0f));

        addChild(_blurSprite);
        addChild(sprite);

        auto label = Label::createWithTTF("Normal Sprite", "fonts/arial.ttf", 12.0f);
        addChild(label);
        label->setPosition(Vec2(2 * s.width / 3, s.height / 3.0f));
        createSliderCtls();

        return true;
    }

    return false;
}

void ShaderBlur::onRadiusChanged(Ref* sender, Control::EventType)
{
    ControlSlider* slider = (ControlSlider*)sender;
    _blurSprite->setBlurRadius(slider->getValue());
}

void ShaderBlur::onSampleNumChanged(Ref* sender, Control::EventType)
{
    ControlSlider* slider = (ControlSlider*)sender;
    _blurSprite->setBlurSampleNum(slider->getValue());
}

// ShaderRetroEffect

ShaderRetroEffect::ShaderRetroEffect() : _label(nullptr), _accum(0.0f) {}

bool ShaderRetroEffect::init()
{
    if (ShaderTestDemo::init())
    {

        auto fragStr = FileUtils::getInstance()->getStringFromFile(
            FileUtils::getInstance()->fullPathForFilename("Shaders/example_HorizontalColor.fsh"));
        char* fragSource = (char*)fragStr.c_str();

        auto program  = ProgramManager::newProgram(positionTextureColor_vert, fragSource, VertexLayoutHelper::setupSprite);
        auto p        = new backend::ProgramState(program);
        auto director = Director::getInstance();
        const auto& screenSizeLocation = p->getUniformLocation("u_screenSize");
        const auto& frameSize          = director->getOpenGLView()->getFrameSize();
        float retinaFactor             = director->getOpenGLView()->getRetinaFactor();
        auto screenSizeInPixels        = frameSize * retinaFactor;
        p->setUniform(screenSizeLocation, &screenSizeInPixels, sizeof(screenSizeInPixels));

        auto s = director->getWinSize();

        _label = Label::createWithBMFont("fonts/west_england-64.fnt", "RETRO EFFECT");
        _label->setAnchorPoint(Vec2::ANCHOR_MIDDLE);
        _label->setProgramState(p);
        AX_SAFE_RELEASE(p);

        _label->setPosition(Vec2(s.width / 2, s.height / 2));

        addChild(_label);

        scheduleUpdate();
        AX_SAFE_RELEASE(program);
        return true;
    }

    return false;
}

void ShaderRetroEffect::update(float dt)
{
    _accum += dt;
    int letterCount = _label->getStringLength();
    for (int i = 0; i < letterCount; ++i)
    {
        auto sprite = _label->getLetter(i);
        if (sprite != nullptr)
        {
            auto oldPosition = sprite->getPosition();
            sprite->setPosition(Vec2(oldPosition.x, sinf(_accum * 2 + i / 2.0) * 20));

            // add fabs() to prevent negative scaling
            float scaleY = (sinf(_accum * 2 + i / 2.0 + 0.707));

            sprite->setScaleY(scaleY);
        }
    }
}

std::string ShaderRetroEffect::title() const
{
    return "Shader: Retro test";
}

std::string ShaderRetroEffect::subtitle() const
{
    return "sin() effect with moving colors";
}

ShaderLensFlare::ShaderLensFlare() {}

std::string ShaderLensFlare::title() const
{
    return "ShaderToy Test";
}

std::string ShaderLensFlare::subtitle() const
{
    return "Lens Flare";
}

bool ShaderLensFlare::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/shadertoy_LensFlare.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));
        sn->setContentSize(Size(s.width / 2, s.height / 2));
        addChild(sn);

        return true;
    }

    return false;
}

//
// ShaderGlow
//
ShaderGlow::ShaderGlow() {}

std::string ShaderGlow::title() const
{
    return "ShaderToy Test";
}

std::string ShaderGlow::subtitle() const
{
    return "Glow";
}

bool ShaderGlow::init()
{
    if (ShaderTestDemo::init())
    {
        auto sn = ShaderNode::shaderNodeWithVertex("", "Shaders/shadertoy_Glow.fsh");

        auto s = Director::getInstance()->getWinSize();
        sn->setPosition(Vec2(s.width / 2, s.height / 2));
        sn->setContentSize(Size(s.width / 2, s.height / 2));
        addChild(sn);

        return true;
    }

    return false;
}

//
// ShaderMultiTexture
//
ShaderMultiTexture::ShaderMultiTexture() : _changedTextureId(0) {}

std::string ShaderMultiTexture::title() const
{
    return "MultiTexture test";
}

std::string ShaderMultiTexture::subtitle() const
{
    return "MultiTexture";
}

ui::Slider* ShaderMultiTexture::createSliderCtl()
{
    auto screenSize = Director::getInstance()->getWinSize();

    ui::Slider* slider = ui::Slider::create();
    slider->loadBarTexture("cocosui/sliderTrack.png");
    slider->loadSlidBallTextures("cocosui/sliderThumb.png", "cocosui/sliderThumb.png", "");
    slider->loadProgressBarTexture("cocosui/sliderProgress.png");
    slider->setPercent(50);

    slider->setPosition(Vec2(screenSize.width / 2.0f, screenSize.height / 3.0f));
    addChild(slider);

    slider->addEventListener([&](Ref* sender, ui::Slider::EventType type) {
        if (type == ui::Slider::EventType::ON_PERCENTAGE_CHANGED)
        {
            ui::Slider* slider = dynamic_cast<ui::Slider*>(sender);
            float p            = slider->getPercent() / 100.0f;
            auto state         = _sprite->getProgramState();
            SET_UNIFORM(state, "u_interpolate", p);
        }
    });
    return slider;
}

bool ShaderMultiTexture::init()
{
    if (ShaderTestDemo::init())
    {
        auto s = Director::getInstance()->getWinSize();

        // Left: normal sprite
        auto left = Sprite::create("Images/grossinis_sister1.png");
        addChild(left);
        left->setPosition(s.width * 1 / 4, s.height / 2);

        // Right: normal sprite
        auto right = Sprite::create("Images/grossinis_sister2.png");
        addChild(right, 0, rightSpriteTag);
        right->setPosition(s.width * 3 / 4, s.height / 2);

        // Center: MultiTexture
        _sprite = Sprite::createWithTexture(left->getTexture());
        addChild(_sprite);
        _sprite->setPosition(Vec2(s.width / 2, s.height / 2));

        auto* fu            = FileUtils::getInstance();
        auto vertexShader   = fu->getStringFromFile("Shaders/example_MultiTexture.vsh");
        auto fragmentShader = fu->getStringFromFile("Shaders/example_MultiTexture.fsh");
        auto program        = ProgramManager::newProgram(vertexShader, fragmentShader, VertexLayoutHelper::setupSprite);
        auto programState   = new backend::ProgramState(program);
        _sprite->setProgramState(programState);

        SET_TEXTURE(programState, "u_tex1", 1, right->getTexture()->getBackendTexture());
        SET_UNIFORM(programState, "u_interpolate", 0.5f);

        // slider
        createSliderCtl();

        // menu
        auto label = Label::createWithTTF(TTFConfig("fonts/arial.ttf"), "change");
        auto mi    = MenuItemLabel::create(label, AX_CALLBACK_1(ShaderMultiTexture::changeTexture, this));
        auto menu  = Menu::create(mi, nullptr);
        addChild(menu);
        menu->setPosition(s.width * 7 / 8, s.height / 2);

        AX_SAFE_RELEASE(programState);
        AX_SAFE_RELEASE(program);
        return true;
    }

    return false;
}

void ShaderMultiTexture::changeTexture(Ref*)
{
    static const int textureFilesCount                       = 3;
    static const std::string textureFiles[textureFilesCount] = {"Images/grossini.png", "Images/grossinis_sister1.png",
                                                                "Images/grossinis_sister2.png"};
    auto texture =
        Director::getInstance()->getTextureCache()->addImage(textureFiles[_changedTextureId++ % textureFilesCount]);
    Sprite* right = dynamic_cast<Sprite*>(getChildByTag(rightSpriteTag));
    right->setTexture(texture);
    auto programState = _sprite->getProgramState();
    SET_TEXTURE(programState, "u_tex1", 1, right->getTexture()->getBackendTexture());
}