/****************************************************************************
**
** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
** Copyright (C) 2015 The Qt Company Ltd and/or its subsidiary(-ies).
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****************************************************************************/

#include "renderview_p.h"
#include <Qt3DRenderer/qmaterial.h>
#include <Qt3DRenderer/qrenderaspect.h>
#include <Qt3DRenderer/qrendertarget.h>
#include <Qt3DRenderer/sphere.h>

#include <Qt3DRenderer/private/cameraselectornode_p.h>
#include <Qt3DRenderer/private/framegraphnode_p.h>
#include <Qt3DRenderer/private/layerfilternode_p.h>
#include <Qt3DRenderer/private/qmeshdata_p.h>
#include <Qt3DRenderer/private/meshdatamanager_p.h>
#include <Qt3DRenderer/private/qparameter_p.h>
#include <Qt3DRenderer/private/rendercameralens_p.h>
#include <Qt3DRenderer/private/rendercommand_p.h>
#include <Qt3DRenderer/private/rendereffect_p.h>
#include <Qt3DRenderer/private/renderentity_p.h>
#include <Qt3DRenderer/private/renderer_p.h>
#include <Qt3DRenderer/private/renderlayer_p.h>
#include <Qt3DRenderer/private/renderlogging_p.h>
#include <Qt3DRenderer/private/renderpassfilternode_p.h>
#include <Qt3DRenderer/private/renderrenderpass_p.h>
#include <Qt3DRenderer/private/renderstate_p.h>
#include <Qt3DRenderer/private/techniquefilternode_p.h>
#include <Qt3DRenderer/private/viewportnode_p.h>

#include <Qt3DRenderer/qparametermapping.h>

#include <Qt3DCore/qentity.h>

#include <QtGui/qsurface.h>

#include <algorithm>

#include <QDebug>

QT_BEGIN_NAMESPACE

namespace Qt3D {
namespace Render {

namespace  {

// TODO: Should we treat lack of layer data as implicitly meaning that an
// entity is in all layers?
bool isEntityInLayers(const RenderEntity *entity, const QStringList &layers)
{
    if (layers.isEmpty())
        return true;

    QList<RenderLayer *> renderLayers = entity->renderComponents<RenderLayer>();
    Q_FOREACH (RenderLayer *layer, renderLayers) {
        if (layer->isEnabled())
            Q_FOREACH (const QString &layerName, layer->layers())
                if (layers.contains(layerName))
                    return true;
    }

    return false;
}

} // anonymouse namespace

RenderView::StandardUniformsPFuncsHash RenderView::ms_standardUniformSetters = RenderView::initializeStandardUniformSetters();
QStringList RenderView::ms_standardAttributesNames = RenderView::initializeStandardAttributeNames();

RenderView::StandardUniformsPFuncsHash RenderView::initializeStandardUniformSetters()
{
    RenderView::StandardUniformsPFuncsHash setters;

    setters.insert(QStringLiteral("modelMatrix"), &RenderView::modelMatrix);
    setters.insert(QStringLiteral("viewMatrix"), &RenderView::viewMatrix);
    setters.insert(QStringLiteral("projectionMatrix"), &RenderView::projectionMatrix);
    setters.insert(QStringLiteral("modelView"), &RenderView::modelViewMatrix);
    setters.insert(QStringLiteral("modelViewProjection"), &RenderView::modelViewProjectionMatrix);
    setters.insert(QStringLiteral("mvp"), &RenderView::modelViewProjectionMatrix);
    setters.insert(QStringLiteral("inverseModelMatrix"), &RenderView::inverseModelMatrix);
    setters.insert(QStringLiteral("inverViewMatrix"), &RenderView::inverseViewMatrix);
    setters.insert(QStringLiteral("inverseProjectionMatrix"), &RenderView::inverseProjectionMatrix);
    setters.insert(QStringLiteral("inverseModelView"), &RenderView::inverseModelViewMatrix);
    setters.insert(QStringLiteral("inverseModelViewProjection"), &RenderView::inverseModelViewProjectionMatrix);
    setters.insert(QStringLiteral("modelNormalMatrix"), &RenderView::modelNormalMatrix);
    setters.insert(QStringLiteral("modelViewNormal"), &RenderView::modelViewNormalMatrix);
    setters.insert(QStringLiteral("viewportMatrix"), &RenderView::viewportMatrix);
    setters.insert(QStringLiteral("inverseViewportMatrix"), &RenderView::inverseViewportMatrix);
    setters.insert(QStringLiteral("time"), &RenderView::time);

    return setters;
}

QStringList RenderView::initializeStandardAttributeNames()
{
    QStringList attributesNames;

    attributesNames << QMeshData::defaultPositionAttributeName();
    attributesNames << QMeshData::defaultTextureCoordinateAttributeName();
    attributesNames << QMeshData::defaultNormalAttributeName();
    attributesNames << QMeshData::defaultColorAttributeName();
    attributesNames << QMeshData::defaultTangentAttributeName();

    return attributesNames;
}

QUniformValue *RenderView::modelMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant(model, m_allocator);
}

QUniformValue *RenderView::viewMatrix(const QMatrix4x4 &) const
{
    return QUniformValue::fromVariant(*m_data->m_viewMatrix, m_allocator);
}

QUniformValue *RenderView::projectionMatrix(const QMatrix4x4 &) const
{
    return QUniformValue::fromVariant(m_data->m_renderCamera->projection(), m_allocator);
}

QUniformValue *RenderView::modelViewMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant(*m_data->m_viewMatrix * model, m_allocator);
}

QUniformValue *RenderView::modelViewProjectionMatrix(const QMatrix4x4 &model) const
{
    QMatrix4x4 projection;
    if (m_data->m_renderCamera)
        projection = m_data->m_renderCamera->projection();
    return QUniformValue::fromVariant(projection * *m_data->m_viewMatrix * model, m_allocator);
}

QUniformValue *RenderView::inverseModelMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant(model.inverted(), m_allocator);
}

QUniformValue *RenderView::inverseViewMatrix(const QMatrix4x4 &) const
{
    return QUniformValue::fromVariant(m_data->m_viewMatrix->inverted(), m_allocator);
}

QUniformValue *RenderView::inverseProjectionMatrix(const QMatrix4x4 &) const
{
    QMatrix4x4 projection;
    if (m_data->m_renderCamera)
        projection = m_data->m_renderCamera->projection();
    return QUniformValue::fromVariant(projection.inverted(), m_allocator);
}

QUniformValue *RenderView::inverseModelViewMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant((*m_data->m_viewMatrix * model).inverted(), m_allocator);
}

QUniformValue *RenderView::inverseModelViewProjectionMatrix(const QMatrix4x4 &model) const
{
    QMatrix4x4 projection;
    if (m_data->m_renderCamera)
        projection = m_data->m_renderCamera->projection();
    return QUniformValue::fromVariant((projection * *m_data->m_viewMatrix * model).inverted(0), m_allocator);
}

QUniformValue *RenderView::modelNormalMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant(QVariant::fromValue(model.normalMatrix()), m_allocator);
}

QUniformValue *RenderView::modelViewNormalMatrix(const QMatrix4x4 &model) const
{
    return QUniformValue::fromVariant(QVariant::fromValue((*m_data->m_viewMatrix * model).normalMatrix()), m_allocator);
}

// TODO: Move this somewhere global where QGraphicsContext::setViewport() can use it too
static QRectF resolveViewport(const QRectF &fractionalViewport, const QSize &surfaceSize)
{
    return QRectF(fractionalViewport.x() * surfaceSize.width(),
                  (1.0 - fractionalViewport.y() - fractionalViewport.height()) * surfaceSize.height(),
                  fractionalViewport.width() * surfaceSize.width(),
                  fractionalViewport.height() * surfaceSize.height());
}

QUniformValue *RenderView::viewportMatrix(const QMatrix4x4 &model) const
{
    // TODO: Can we avoid having to pass the model matrix in to these functions?
    Q_UNUSED(model);
    QMatrix4x4 viewportMatrix;
    viewportMatrix.viewport(resolveViewport(*m_viewport, m_surfaceSize));
    return QUniformValue::fromVariant(QVariant::fromValue(viewportMatrix), m_allocator);

}

QUniformValue *RenderView::inverseViewportMatrix(const QMatrix4x4 &model) const
{
    Q_UNUSED(model);
    QMatrix4x4 viewportMatrix;
    viewportMatrix.viewport(resolveViewport(*m_viewport, m_surfaceSize));
    QMatrix4x4 inverseViewportMatrix = viewportMatrix.inverted();
    return QUniformValue::fromVariant(QVariant::fromValue(inverseViewportMatrix), m_allocator);

}

QUniformValue *RenderView::time(const QMatrix4x4 &model) const
{
    Q_UNUSED(model);
    qint64 time = m_renderer->rendererAspect()->time();
    float t = time / 1000000000.0f;
    return QUniformValue::fromVariant(QVariant(t), m_allocator);
}

RenderView::RenderView()
    : m_renderer(Q_NULLPTR)
    , m_allocator(Q_NULLPTR)
    , m_data(Q_NULLPTR)
    , m_clearColor(Q_NULLPTR)
    , m_viewport(Q_NULLPTR)
    , m_clearBuffer(QClearBuffer::None)
    , m_stateSet(Q_NULLPTR)
    , m_noDraw(false)
{
}

RenderView::~RenderView()
{
    if (m_allocator == Q_NULLPTR) // Mainly needed for unit tests
        return;

    Q_FOREACH (RenderCommand *command, m_commands) {
        // Deallocate all uniform values of the QUniformPack of each RenderCommand
        const QHash<QString, const QUniformValue* > uniforms = command->m_uniforms.uniforms();
        const QHash<QString, const QUniformValue* >::const_iterator end = uniforms.constEnd();
        QHash<QString, const QUniformValue* >::const_iterator it = uniforms.constBegin();
        for (; it != end; ++it)
            m_allocator->deallocate<QUniformValue>(const_cast<QUniformValue *>(it.value()));

        if (command->m_stateSet != Q_NULLPTR) // We do not delete the RenderState as that is stored statically
            m_allocator->deallocate<RenderStateSet>(command->m_stateSet);

        // Deallocate RenderCommand
        m_allocator->deallocate<RenderCommand>(command);
    }

    // Deallocate viewMatrix
    m_allocator->deallocate<QMatrix4x4>(m_data->m_viewMatrix);
    // Deallocate viewport rect
    m_allocator->deallocate<QRectF>(m_viewport);
    // Deallocate clearColor
    m_allocator->deallocate<QColor>(m_clearColor);
    // Deallocate m_data
    m_allocator->deallocate<InnerData>(m_data);
    // Deallocate m_stateSet
    if (m_stateSet)
        m_allocator->deallocate<RenderStateSet>(m_stateSet);
}

// We need to overload the delete operator so that when the Renderer deletes the list of RenderViews, each RenderView
// can clear itself with the frame allocator and deletes its RenderViews
void RenderView::operator delete(void *ptr)
{
    RenderView *rView = static_cast<RenderView *>(ptr);
    if (rView != Q_NULLPTR && rView->m_allocator != Q_NULLPTR)
        rView->m_allocator->deallocateRawMemory(rView, sizeof(RenderView));
}

// Since placement new is used we need a matching operator delete, at least MSVC complains otherwise
void RenderView::operator delete(void *ptr, void *)
{
    RenderView *rView = static_cast<RenderView *>(ptr);
    if (rView != Q_NULLPTR && rView->m_allocator != Q_NULLPTR)
        rView->m_allocator->deallocateRawMemory(rView, sizeof(RenderView));
}

void RenderView::sort()
{
    // Compares the bitsetKey of the RenderCommands
    // Key[Depth | StateCost | Shader]
    std::sort(m_commands.begin(), m_commands.end(), compareCommands);

    // Minimize uniform changes
    int i = 0;
    while (i < m_commands.size()) {
        int j = i;

        // Advance while commands share the same shader
        while (i < m_commands.size() && m_commands[j]->m_shaderDna == m_commands[i]->m_shaderDna)
            ++i;

        if (i - j > 0) { // Several commands have the same shader, so we minimize uniform changes
            QHash<QString, const QUniformValue *> cachedUniforms = m_commands[j++]->m_uniforms.uniforms();

            while (j < i) {
                QHash<QString, const QUniformValue *> &uniforms = m_commands[j]->m_uniforms.uniforms();
                QHash<QString, const QUniformValue *>::iterator it = uniforms.begin();

                while (it != uniforms.end()) {
                    bool found = false;
                    if (cachedUniforms.contains(it.key()) && !it.value()->isTexture()) {
                        const QUniformValue *refValue = cachedUniforms[it.key()];
                        if (*const_cast<QUniformValue *>(refValue) == *it.value()) {
                            cachedUniforms.insert(it.key(), it.value());
                            it = uniforms.erase(it);
                            found = true;
                        }
                    }
                    if (!found) {
                        cachedUniforms.insert(it.key(), it.value());
                        ++it;
                    }
                }
                ++j;
            }
        }
        ++i;
    }
}

void RenderView::setRenderer(Renderer *renderer)
{
    m_renderer = renderer;
    m_data->m_uniformBlockBuilder.shaderDataManager = m_renderer->shaderDataManager();
}

// Tries to order renderCommand by shader so as to minimize shader changes
void RenderView::buildRenderCommands(RenderEntity *node)
{
    // Build renderCommand for current node
    if (isEntityInLayers(node, m_data->m_layers)) {
        RenderMesh *mesh = Q_NULLPTR;
        if (node->componentHandle<RenderMesh, 16>() != HMesh()
                && (mesh = node->renderComponent<RenderMesh>()) != Q_NULLPTR
                && mesh->isEnabled()) {
            if (!mesh->meshDataHandle().isNull()) {
                // TO DO: Perform culling here
                // As shaders may be deforming, transforming the mesh
                // We might want to make that optional or dependent on an explicit bounding box item

                // Find the material, effect, technique and set of render passes to use
                RenderMaterial *material = Q_NULLPTR;
                RenderEffect *effect = Q_NULLPTR;
                if ((material = node->renderComponent<RenderMaterial>()) != Q_NULLPTR && material->isEnabled())
                    effect = m_renderer->effectManager()->lookupResource(material->effect());
                RenderTechnique *technique = findTechniqueForEffect(m_renderer, this, effect);

                ParameterInfoList parameters;
                // Order set:
                // 1 Pass Filter
                // 2 Technique Filter
                // 3 Material
                // 4 Effect
                // 5 Technique
                // 6 RenderPass

                // Add Parameters define in techniqueFilter and passFilter
                // passFilter have priority over techniqueFilter
                if (m_data->m_passFilter)
                    parametersFromParametersProvider(&parameters, m_renderer->parameterManager(),
                                                     m_data->m_passFilter);
                if (m_data->m_techniqueFilter)
                    parametersFromParametersProvider(&parameters, m_renderer->parameterManager(),
                                                     m_data->m_techniqueFilter);

                RenderRenderPassList passes;
                if (technique) {
                    passes = findRenderPassesForTechnique(m_renderer, this, technique);
                } else {
                    material = m_renderer->materialManager()->data(m_renderer->defaultMaterialHandle());
                    effect = m_renderer->effectManager()->data(m_renderer->defaultEffectHandle());
                    technique = m_renderer->techniqueManager()->data(m_renderer->defaultTechniqueHandle());
                    passes << m_renderer->renderPassManager()->data(m_renderer->defaultRenderPassHandle());
                }

                // Get the parameters for our selected rendering setup (override what was defined in the technique/pass filter)
                parametersFromMaterialEffectTechnique(&parameters, m_renderer->parameterManager(), material, effect, technique);

                // 1 RenderCommand per RenderPass pass on an Entity with a Mesh
                Q_FOREACH (RenderRenderPass *pass, passes) {

                    // Add the RenderRenderPass Parameters
                    ParameterInfoList globalParameter = parameters;
                    parametersFromParametersProvider(&globalParameter, m_renderer->parameterManager(), pass);

                    RenderCommand *command = m_allocator->allocate<RenderCommand>();
                    command->m_depth = m_data->m_eyePos.distanceToPoint(node->worldBoundingVolume()->center());
                    command->m_meshData = mesh->meshDataHandle();
                    command->m_instancesCount = 0;
                    command->m_stateSet = Q_NULLPTR;
                    command->m_changeCost = 0;
                    // For RenderPass based states we use the globally set RenderState
                    // if no renderstates are defined as part of the pass. That means:
                    // RenderPass { renderStates: [] } will use the states defined by
                    // StateSet in the FrameGraph
                    if (!pass->renderStates().isEmpty())
                        command->m_stateSet = buildRenderStateSet(pass->renderStates(), m_allocator);
                    if (command->m_stateSet != Q_NULLPTR) {
                        // Merge per pass stateset with global stateset
                        // so that the local stateset only overrides
                        if (m_stateSet != Q_NULLPTR)
                            command->m_stateSet->merge(m_stateSet);
                        command->m_changeCost = m_renderer->defaultRenderState()->changeCost(command->m_stateSet);
                    }
                    setShaderAndUniforms(command, pass, parameters, *(node->worldTransform()));
                    buildSortingKey(command);
                    m_commands.append(command);
                }
            }
        }
    }

    // Traverse children
    Q_FOREACH (RenderEntity *child, node->children())
        buildRenderCommands(child);
}

const AttachmentPack &RenderView::attachmentPack() const
{
    return m_attachmentPack;
}

void RenderView::setUniformValue(QUniformPack &uniformPack, const QString &name, const QVariant &value)
{
    RenderTexture *tex = Q_NULLPTR;
    if ((tex = value.value<RenderTexture *>()) != Q_NULLPTR) {
        uniformPack.setTexture(name, tex->peerUuid());
        TextureUniform *texUniform = m_allocator->allocate<TextureUniform>();
        texUniform->setTextureId(tex->peerUuid());
        uniformPack.setUniform(name, texUniform);
    } else {
        uniformPack.setUniform(name, QUniformValue::fromVariant(value, m_allocator));
    }
}

void RenderView::setUniformBlockValue(QUniformPack &uniformPack, RenderShader *shader, const ShaderUniformBlock &block, const QVariant &value)
{
    RenderShaderData *shaderData = Q_NULLPTR;
    if ((shaderData = value.value<RenderShaderData *>())) {
        // UBO are indexed by <ShaderId, ShaderDataId> so that a same QShaderData can be used among different shaders
        // while still making sure that if they have a different layout everything will still work
        // If two shaders define the same block with the exact same layout, in that case the UBO could be shared
        // but how do we know that ? We'll need to compare ShaderUniformBlocks

        // For now a UBO is unique to a Shader and a ShaderData
        // later we might want to make them shareable across Shaders but
        // that will require checking that all Shaders have the same layout for a given
        // uniform block
        ShaderDataShaderUboKey uboKey(shaderData->peerUuid(),
                                      shader->peerUuid());

        BlockToUBO uniformBlockUBO;
        uniformBlockUBO.m_blockIndex = block.m_index;
        uniformBlockUBO.m_shaderDataID = shaderData->peerUuid();
        bool uboNeedsUpdate = false;

        // build UBO at uboId if not created before
        if (!m_renderer->uboManager()->contains(uboKey)) {
            m_renderer->uboManager()->getOrCreateResource(uboKey);
            uboNeedsUpdate = true;
        }

        // If shaderData  has been updated (property has changed or one of the nested properties has changed)
        // foreach property defined in the QShaderData, we try to fill the value of the corresponding active uniform(s)
        // for all the updated properties (all the properties if the UBO was just created)
        if (shaderData->needsUpdate(*m_data->m_viewMatrix) || uboNeedsUpdate) {
            // Clear previous values remaining in the hash
            m_data->m_uniformBlockBuilder.activeUniformNamesToValue.clear();
            // Update only update properties if uboNeedsUpdate is true, otherwise update the whole block
            m_data->m_uniformBlockBuilder.updatedPropertiesOnly = uboNeedsUpdate;
            // Retrieve names and description of each active uniforms in the uniform block
            m_data->m_uniformBlockBuilder.uniforms = shader->activeUniformsForBlock(block.m_index);
            // Builds the name-value map for the block
            m_data->m_uniformBlockBuilder.buildActiveUniformNameValueMapStructHelper(shaderData, block.m_name);
            if (!uboNeedsUpdate)
                shaderData->addToClearUpdateList();
            // copy the name-value map into the BlockToUBO
            uniformBlockUBO.m_updatedProperties = m_data->m_uniformBlockBuilder.activeUniformNamesToValue;
            uboNeedsUpdate = true;
        }

        uniformBlockUBO.m_needsUpdate = uboNeedsUpdate;
        uniformPack.setUniformBuffer(uniformBlockUBO);
    }
}

void RenderView::setDefaultUniformBlockShaderDataValue(QUniformPack &uniformPack, RenderShader *shader, RenderShaderData *shaderData, const QString &structName)
{
    m_data->m_uniformBlockBuilder.activeUniformNamesToValue.clear();

    // updates transformed properties;
    shaderData->needsUpdate(*m_data->m_viewMatrix);
    // Force to update the whole block
    m_data->m_uniformBlockBuilder.updatedPropertiesOnly = false;
    // Retrieve names and description of each active uniforms in the uniform block
    m_data->m_uniformBlockBuilder.uniforms = shader->activeUniformsForBlock(-1);
    // Build name-value map for the block
    m_data->m_uniformBlockBuilder.buildActiveUniformNameValueMapStructHelper(shaderData, structName);
    // Set uniform values for each entrie of the block name-value map
    QHash<QString, QVariant>::const_iterator activeValuesIt = m_data->m_uniformBlockBuilder.activeUniformNamesToValue.begin();
    const QHash<QString, QVariant>::const_iterator activeValuesEnd = m_data->m_uniformBlockBuilder.activeUniformNamesToValue.end();

    while (activeValuesIt != activeValuesEnd) {
        setUniformValue(uniformPack, activeValuesIt.key(), activeValuesIt.value());
        ++activeValuesIt;
    }
}

void RenderView::buildSortingKey(RenderCommand *command)
{
    // Build a bitset key depending on the SortingCriterion
    int sortCount = m_data->m_sortingCriteria.count();

    // If sortCount == 0, no sorting is applied

    // Handle at most 4 filters at once
    for (int i = 0; i < sortCount && i < 4; i++) {
        SortCriterion *sC = m_renderer->sortCriterionManager()->lookupResource(m_data->m_sortingCriteria[i]);

        switch (sC->sortType()) {
        case QSortCriterion::StateChangeCost:
            command->m_sortingType.sorts[i] = command->m_changeCost; // State change cost
            break;
        case QSortCriterion::BackToFront:
            command->m_sortingType.sorts[i] = 0; // Depth value (not implemented yet)
            break;
        case QSortCriterion::Material:
            command->m_sortingType.sorts[i] = command->m_shaderDna; // Material
            break;
        default:
            Q_UNREACHABLE();
        }
    }
}

void RenderView::setShaderAndUniforms(RenderCommand *command, RenderRenderPass *rPass, ParameterInfoList &parameters, const QMatrix4x4 &worldTransform)
{
    // The VAO Handle is set directly in the renderer thread so as to avoid having to use a mutex here
    // Set shader, technique, and effect by basically doing :
    // ShaderProgramManager[MaterialManager[frontentEntity->id()]->Effect->Techniques[TechniqueFilter->name]->RenderPasses[RenderPassFilter->name]];
    // The Renderer knows that if one of those is null, a default material / technique / effect as to be used

    // Find all RenderPasses (in order) matching values set in the RenderPassFilter
    // Get list of parameters for the Material, Effect, and Technique
    // For each ParameterBinder in the RenderPass -> create a QUniformPack
    // Once that works, improve that to try and minimize QUniformPack updates

    if (rPass != Q_NULLPTR) {
        // Index RenderShader by Shader UUID
        command->m_shader = m_renderer->shaderManager()->lookupHandle(rPass->shaderProgram());
        RenderShader *shader = Q_NULLPTR;
        if ((shader = m_renderer->shaderManager()->data(command->m_shader)) != Q_NULLPTR) {

            command->m_shaderDna = shader->dna();

            // Builds the QUniformPack, sets shader standard uniforms and store attributes name / glname bindings
            // If a parameter is defined and not found in the bindings it is assumed to be a binding of Uniform type with the glsl name
            // equals to the parameter name
            const QVector<QString> &uniformNames = shader->uniformsNames();
            const QVector<QString> &attributeNames = shader->attributesNames();
            const QVector<QString> &uniformBlockNames = shader->uniformBlockNames();

            // Set fragData Name and index
            // Later on we might want to relink the shader if attachments have changed
            // But for now we set them once and for all
            QHash<QString, int> fragOutputs;
            if (!m_renderTarget.isNull() && !shader->isLoaded()) {
                Q_FOREACH (const Attachment &att, m_attachmentPack.attachments()) {
                    if (att.m_type <= QRenderAttachment::ColorAttachment15)
                        fragOutputs.insert(att.m_name, att.m_type);
                }
            }

            if (!uniformNames.isEmpty() || !attributeNames.isEmpty()) {

                // Set default standard uniforms without bindings
                Q_FOREACH (const QString &uniformName, uniformNames) {
                    if (ms_standardUniformSetters.contains(uniformName))
                        command->m_uniforms.setUniform(uniformName,
                                                       (this->*ms_standardUniformSetters[uniformName])(worldTransform));
                }

                // Set default attributes
                Q_FOREACH (const QString &attributeName, attributeNames) {
                    if (ms_standardAttributesNames.contains(attributeName))
                        command->m_parameterAttributeToShaderNames.insert(attributeName, attributeName);
                }

                // Set uniforms and attributes explicitly binded
                Q_FOREACH (const RenderParameterMapping &binding, rPass->bindings()) {
                    ParameterInfoList::iterator it = findParamInfo(&parameters, binding.parameterName());
                    if (it == parameters.end()) {
                        if (binding.bindingType() == QParameterMapping::Attribute
                                && attributeNames.contains(binding.shaderVariableName())) {
                            command->m_parameterAttributeToShaderNames.insert(binding.parameterName(), binding.shaderVariableName());
                        } else if (binding.bindingType() == QParameterMapping::StandardUniform
                                   && uniformNames.contains(binding.shaderVariableName())
                                   && ms_standardUniformSetters.contains(binding.parameterName())) {
                            command->m_uniforms.setUniform(binding.shaderVariableName(),
                                                           (this->*ms_standardUniformSetters[binding.parameterName()])(worldTransform));
                        } else if (binding.bindingType() == QParameterMapping::FragmentOutput
                                   && fragOutputs.contains(binding.parameterName())) {
                            fragOutputs.insert(binding.shaderVariableName(), fragOutputs.take(binding.parameterName()));
                        } else {
                            qCWarning(Render::Backend) << Q_FUNC_INFO << "Trying to bind a Parameter that hasn't been defined " << binding.parameterName();
                        }
                    } else {
                        setUniformValue(command->m_uniforms, binding.shaderVariableName(), it->value);
                        parameters.erase(it);
                    }
                }

                // Parameters remaining could be
                // -> uniform scalar / vector
                // -> uniform struct / arrays
                // -> uniform block / array (4.3)

                if ((!uniformNames.isEmpty() || !uniformBlockNames.isEmpty()) && !parameters.isEmpty()) {
                    ParameterInfoList::iterator it = parameters.begin();
                    while (it != parameters.end()) {
                        if (uniformNames.contains(it->name)) { // Parameter is a regular uniform
                            setUniformValue(command->m_uniforms, it->name, it->value);
                            it = parameters.erase(it);
                        } else if (uniformBlockNames.indexOf(it->name) != -1) { // Parameter is a uniform block
                            const ShaderUniformBlock &block = shader->uniformBlock(it->name);
                            setUniformBlockValue(command->m_uniforms, shader, block, it->value);
                            it = parameters.erase(it);
                        } else {
                            const QVariant &v = it->value;
                            RenderShaderData *shaderData = Q_NULLPTR;
                            if ((shaderData = v.value<RenderShaderData *>()) != Q_NULLPTR) {
                                // Try to check if we have a struct or array matching a QShaderData parameter
                                setDefaultUniformBlockShaderDataValue(command->m_uniforms, shader, shaderData, it->name);
                                it = parameters.erase(it);
                            } else {
                                // Else param unused by current shader
                                ++it;
                            }
                        }
                    }
                }
            }
            // Set frag outputs in the shaders if hash not empty
            if (!fragOutputs.isEmpty())
                shader->setFragOutputs(fragOutputs);
        }
    }
    else {
        qCWarning(Render::Backend) << Q_FUNC_INFO << "Using default effect as none was provided";
    }
}

} // namespace Render
} // namespace Qt3D

QT_END_NAMESPACE
