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++ // Copyright (C) 2023 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
++
++ #include "rhirenderingextension.h"
++ #include "cube.h"
++ #include <rhi/qrhi.h>
++ #include <QGuiApplication>
++ #include <ssg/qssgrendercontextcore.h>
++ #include <ssg/qssgrenderextensions.h>
++ #include <ssg/qssgrenderhelpers.h>
++
++ class Renderer : public QSSGRenderExtension
++ {
++ public:
++ Renderer();
++ ~Renderer();
++
++ bool prepareData(QSSGFrameData &data) override;
++ void prepareRender(QSSGFrameData &data) override;
++ void render(QSSGFrameData &data) override;
++ void resetForFrame() override;
++ RenderMode mode() const override { return RenderMode::Main; }
++ RenderStage stage() const override { return renderStage; }
++
++ bool canRender = false;
++ QMatrix4x4 viewProjection;
++ QRhiViewport mainViewport;
++
++ std::unique_ptr<QRhiBuffer> vbuf;
++ std::unique_ptr<QRhiBuffer> ubuf;
++ std::unique_ptr<QRhiShaderResourceBindings> srb;
++ std::unique_ptr<QRhiGraphicsPipeline> ps;
++ QVector<quint32> rpFormat;
++
++ QMatrix4x4 modelMatrix;
++ void updateModelMatrix(const QVector3D &pos)
++ {
++ modelMatrix.setToIdentity();
++ modelMatrix.translate(pos);
++ modelMatrix.scale(10, 10, 10);
++ }
++
++ RenderStage renderStage = RenderStage::PostColor;
++ };
++
++ Renderer::Renderer()
++ {
++ qDebug() << "Renderer ctor; current thread:" << QThread::currentThread() << "main thread:" << qGuiApp->thread();
++ }
++
++ Renderer::~Renderer()
++ {
++ qDebug() << "Renderer dtor; current thread:" << QThread::currentThread() << "main thread:" << qGuiApp->thread();
++ }
++
++ bool Renderer::prepareData(QSSGFrameData &data)
++ {
++ auto camera = data.activeCamera();
++ if (camera == QSSGCameraId::Invalid) {
++ canRender = false;
++ return false;
++ }
++
++ // ### would be nice to know that we do not have to query (recalculate) every time, if the camera has not changed
++ viewProjection = QSSGCameraHelpers::getViewProjectionMatrix(camera);
++
++ canRender = true;
++
++ return true;
++ }
++
++ static QShader getShader(const QString &name)
++ {
++ QFile f(name);
++ return f.open(QIODevice::ReadOnly) ? QShader::fromSerialized(f.readAll()) : QShader();
++ }
++
++ void Renderer::prepareRender(QSSGFrameData &data)
++ {
++ if (!canRender)
++ return;
++
++ const std::unique_ptr<QSSGRhiContext> &rhiCtx = data.contextInterface()->rhiContext();
++ if (!rhiCtx)
++ return;
++
++ QRhi *rhi = rhiCtx->rhi();
++ QRhiCommandBuffer *cb = rhiCtx->commandBuffer();
++ QRhiResourceUpdateBatch *resourceUpdates = rhi->nextResourceUpdateBatch();
++
++ // The SceneEnvironment changes the MSAA setting dynamically. To follow
++ // this, we need this extra check so that we can recreate the graphics
++ // pipeline with the correct sample count upon a change.
++ if (ps && ps->sampleCount() != rhiCtx->mainPassSampleCount())
++ ps.reset();
++
++ // This is not strictly required for this application. However, if there is
++ // a chance that the View3D moves to become a (texture-backed) layer, part
++ // of a ShaderEffect, or gets moved to a new window, robust implementations
++ // should prepare for that like this, since some render target parameters
++ // may be different then, which may imply that the graphics pipeline needs
++ // to be recreated.
++ QVector<quint32> currentRpFormat = rhiCtx->mainRenderPassDescriptor()->serializedFormat();
++ if (ps && rpFormat != currentRpFormat)
++ ps.reset();
++
++ if (!ps) {
++ vbuf.reset(rhi->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(cube)));
++ vbuf->create();
++
++ resourceUpdates->uploadStaticBuffer(vbuf.get(), cube);
++
++ ubuf.reset(rhi->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, 64 + 16));
++ ubuf->create();
++
++ srb.reset(rhi->newShaderResourceBindings());
++ srb->setBindings({
++ QRhiShaderResourceBinding::uniformBuffer(0, QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage, ubuf.get()),
++ });
++ srb->create();
++
++ ps.reset(rhi->newGraphicsPipeline());
++ // depth testing is important since we test against the objects already rendered by the View3D. (the mode is Overlay)
++ ps->setDepthTest(true);
++ ps->setDepthWrite(true);
++ ps->setCullMode(QRhiGraphicsPipeline::Back);
++ ps->setShaderStages({
++ { QRhiShaderStage::Vertex, getShader(QLatin1String(":/shaders/solidcolor.vert.qsb")) },
++ { QRhiShaderStage::Fragment, getShader(QLatin1String(":/shaders/solidcolor.frag.qsb")) }
++ });
++ QRhiVertexInputLayout inputLayout;
++ inputLayout.setBindings({
++ { 3 * sizeof(float) }
++ });
++ inputLayout.setAttributes({
++ { 0, 0, QRhiVertexInputAttribute::Float3, 0 }
++ });
++ ps->setVertexInputLayout(inputLayout);
++ ps->setShaderResourceBindings(srb.get());
++
++ // Must play nice with the View3D's render target.
++ ps->setRenderPassDescriptor(rhiCtx->mainRenderPassDescriptor());
++ rpFormat = currentRpFormat;
++ ps->setSampleCount(rhiCtx->mainPassSampleCount());
++
++ ps->create();
++ }
++
++ // clipSpaceCorrMatrix has to be applied manually
++ QMatrix4x4 mvp = rhi->clipSpaceCorrMatrix() * viewProjection * modelMatrix;
++ resourceUpdates->updateDynamicBuffer(ubuf.get(), 0, 64, mvp.constData());
++
++ QVector4D color(0, 0.5f, 0, 1);
++ resourceUpdates->updateDynamicBuffer(ubuf.get(), 64, 16, &color);
++
++ cb->resourceUpdate(resourceUpdates);
++
++ mainViewport = data.getPipelineState().viewport;
++ }
++
++ void Renderer::render(QSSGFrameData &data)
++ {
++ if (!canRender)
++ return;
++
++ const std::unique_ptr<QSSGRhiContext> &rhiCtx = data.contextInterface()->rhiContext();
++ if (!rhiCtx)
++ return;
++
++ QRhiCommandBuffer *cb = rhiCtx->commandBuffer();
++
++ // this is within a renderpass since the extension type is Main (not Standalone)
++
++ cb->debugMarkBegin(QByteArrayLiteral("Custom rhi rendering"));
++
++ cb->setGraphicsPipeline(ps.get());
++ cb->setViewport(mainViewport);
++ cb->setShaderResources();
++ const QRhiCommandBuffer::VertexInput vbufBindings[] = {
++ { vbuf.get(), 0 }
++ };
++ cb->setVertexInput(0, 1, vbufBindings);
++ cb->draw(36);
++
++ cb->debugMarkEnd();
++ }
++
++ void Renderer::resetForFrame()
++ {
++ }
++
++ QSSGRenderGraphObject *RhiRenderingExtension::updateSpatialNode(QSSGRenderGraphObject *node)
++ {
++ if (!node)
++ node = new Renderer;
++
++ Renderer *renderer = static_cast<Renderer *>(node);
++
++ if (m_dirtyFlag & PositionDirty)
++ renderer->updateModelMatrix(QVector3D(m_x, m_y, m_z));
++
++ if (m_dirtyFlag & ModeDirty) {
++ // the difference is obvious when the sphere is semi-transparent and the cube overlaps with it
++ switch (m_mode) {
++ case Overlay:
++ renderer->renderStage = QSSGRenderExtension::RenderStage::PostColor;
++ break;
++ case Underlay:
++ renderer->renderStage = QSSGRenderExtension::RenderStage::PreColor;
++ break;
++ }
++ }
++
++ m_dirtyFlag = {};
++
++ return node;
++ }
++
++ void RhiRenderingExtension::markDirty(Dirty v)
++ {
++ m_dirtyFlag |= v;
++ update();
++ }