1 files changed, 199 insertions, 0 deletions
diff --git a/tests/manual/rhi/displacement/displacement.cpp b/tests/manual/rhi/displacement/displacement.cpp
new file mode 100644
index 0000000000..680ffa0628
--- /dev/null
+++ b/tests/manual/rhi/displacement/displacement.cpp
@@ -0,0 +1,199 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#define EXAMPLEFW_IMGUI
+#include "../shared/examplefw.h"
+#include "../shared/cube.h"
+
+// Another tessellation test. Compatible with Direct 3D via hand-written hull
+// and domain shaders, but this already pushes the limits of what is sensible
+// when it comes to injecting hand-written HLSL code to get tessellation
+// functional (cbuffer layout, resource registers all need to be figured out
+// manually and works only as long as the GLSL source is not changing, etc.).
+// Note that the domain shader must use SampleLevel (textureLod), it won't
+// compile for ds_5_0 otherwise.
+
+static const quint32 UBUF_SIZE = 80;
+
+struct {
+    QList<QRhiResource *> releasePool;
+
+    QRhiBuffer *vbuf;
+    QRhiBuffer *ubuf;
+    QRhiTexture *tex;
+    QRhiSampler *sampler;
+    QRhiShaderResourceBindings *srb;
+    QRhiGraphicsPipeline *psWire;
+    QRhiGraphicsPipeline *psSolid;
+    bool rotate = true;
+    float rotation = 0.0f;
+    float viewZ = 0.0f;
+    float displacementAmount = 0.0f;
+    int tessInner = 4;
+    int tessOuter = 4;
+    bool useTex = false;
+    bool wireframe = true;
+
+    QRhiResourceUpdateBatch *initialUpdates = nullptr;
+} d;
+
+void Window::customInit()
+{
+    if (!m_r->isFeatureSupported(QRhi::Tessellation))
+        qFatal("Tessellation is not supported");
+
+    d.initialUpdates = m_r->nextResourceUpdateBatch();
+
+    d.vbuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(cube));
+    d.vbuf->create();
+    d.releasePool << d.vbuf;
+
+    d.initialUpdates->uploadStaticBuffer(d.vbuf, cube);
+
+    d.ubuf = m_r->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, m_r->ubufAligned(UBUF_SIZE));
+    d.ubuf->create();
+    d.releasePool << d.ubuf;
+
+    QImage image;
+    image.load(":/heightmap.png");
+    if (image.isNull())
+        qFatal("Failed to load displacement map");
+
+    d.tex = m_r->newTexture(QRhiTexture::RGBA8, image.size());
+    d.tex->create();
+    d.releasePool << d.tex;
+
+    d.initialUpdates->uploadTexture(d.tex, image);
+
+    d.sampler = m_r->newSampler(QRhiSampler::Linear, QRhiSampler::Linear, QRhiSampler::None,
+                                QRhiSampler::Repeat, QRhiSampler::Repeat);
+    d.releasePool << d.sampler;
+    d.sampler->create();
+
+    d.srb = m_r->newShaderResourceBindings();
+    d.releasePool << d.srb;
+    d.srb->setBindings({
+            QRhiShaderResourceBinding::uniformBuffer(0,
+                           QRhiShaderResourceBinding::TessellationControlStage
+                           | QRhiShaderResourceBinding::TessellationEvaluationStage,
+                           d.ubuf),
+            QRhiShaderResourceBinding::sampledTexture(1, QRhiShaderResourceBinding::TessellationEvaluationStage, d.tex, d.sampler)
+        });
+    d.srb->create();
+
+    QRhiVertexInputLayout inputLayout;
+    inputLayout.setBindings({
+        { 3 * sizeof(float) },
+        { 2 * sizeof(float) },
+        { 3 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float3, 0 },
+        { 1, 1, QRhiVertexInputAttribute::Float2, 0 },
+        { 2, 2, QRhiVertexInputAttribute::Float3, 0 }
+    });
+
+    const QRhiShaderStage stages[] = {
+        { QRhiShaderStage::Vertex, getShader(QLatin1String(":/material.vert.qsb")) },
+        { QRhiShaderStage::TessellationControl, getShader(QLatin1String(":/material.tesc.qsb")) },
+        { QRhiShaderStage::TessellationEvaluation, getShader(QLatin1String(":/material.tese.qsb")) },
+        { QRhiShaderStage::Fragment, getShader(QLatin1String(":/material.frag.qsb")) }
+    };
+
+    d.psWire = m_r->newGraphicsPipeline();
+    d.releasePool << d.psWire;
+    d.psWire->setTopology(QRhiGraphicsPipeline::Patches);
+    d.psWire->setPatchControlPointCount(3);
+    d.psWire->setShaderStages(stages, stages + 4);
+    d.psWire->setDepthTest(true);
+    d.psWire->setDepthWrite(true);
+    d.psWire->setCullMode(QRhiGraphicsPipeline::Back);
+    d.psWire->setPolygonMode(QRhiGraphicsPipeline::Line);
+    d.psWire->setVertexInputLayout(inputLayout);
+    d.psWire->setShaderResourceBindings(d.srb);
+    d.psWire->setRenderPassDescriptor(m_rp);
+    d.psWire->create();
+
+    d.psSolid = m_r->newGraphicsPipeline();
+    d.releasePool << d.psSolid;
+    d.psSolid->setTopology(QRhiGraphicsPipeline::Patches);
+    d.psSolid->setPatchControlPointCount(3);
+    d.psSolid->setShaderStages(stages, stages + 4);
+    d.psSolid->setDepthTest(true);
+    d.psSolid->setDepthWrite(true);
+    d.psSolid->setCullMode(QRhiGraphicsPipeline::Back);
+    d.psSolid->setVertexInputLayout(inputLayout);
+    d.psSolid->setShaderResourceBindings(d.srb);
+    d.psSolid->setRenderPassDescriptor(m_rp);
+    d.psSolid->create();
+}
+
+void Window::customRelease()
+{
+    qDeleteAll(d.releasePool);
+    d.releasePool.clear();
+}
+
+void Window::customRender()
+{
+    const QSize outputSizeInPixels = m_sc->currentPixelSize();
+    QRhiCommandBuffer *cb = m_sc->currentFrameCommandBuffer();
+    QRhiResourceUpdateBatch *u = nullptr;
+    if (d.initialUpdates) {
+        u = d.initialUpdates;
+        d.initialUpdates = nullptr;
+    }
+
+    char *p = d.ubuf->beginFullDynamicBufferUpdateForCurrentFrame();
+    QMatrix4x4 mvp = m_proj;
+    mvp.translate(0, 0, d.viewZ);
+    mvp.rotate(d.rotation, 1, 1, 0);
+    mvp.scale(0.5f);
+
+    memcpy(p, mvp.constData(), 64);
+    memcpy(p + 64, &d.displacementAmount, sizeof(float));
+    float tessInnerFloat = d.tessInner;
+    memcpy(p + 68, &tessInnerFloat, sizeof(float));
+    float tessOuterFloat = d.tessOuter;
+    memcpy(p + 72, &tessOuterFloat, sizeof(float));
+    qint32 useTex = d.useTex ? 1 : 0;
+    memcpy(p + 76, &useTex, sizeof(qint32));
+
+    d.ubuf->endFullDynamicBufferUpdateForCurrentFrame();
+
+    const QRhiCommandBuffer::VertexInput vbufBinding[] = {
+        { d.vbuf, 0 },
+        { d.vbuf, quint32(36 * 3 * sizeof(float)) },
+        { d.vbuf, quint32(36 * (3 + 2) * sizeof(float)) }
+    };
+
+    cb->beginPass(m_sc->currentFrameRenderTarget(), m_clearColor, { 1.0f, 0 }, u, QRhiCommandBuffer::DoNotTrackResourcesForCompute);
+
+    cb->setGraphicsPipeline(d.wireframe ? d.psWire : d.psSolid);
+    cb->setViewport({ 0, 0, float(outputSizeInPixels.width()), float(outputSizeInPixels.height()) });
+    cb->setShaderResources(d.srb);
+    cb->setVertexInput(0, 3, vbufBinding);
+    cb->draw(36);
+
+    m_imguiRenderer->render();
+
+    cb->endPass();
+
+    if (d.rotate)
+        d.rotation += 1;
+}
+
+void Window::customGui()
+{
+    ImGui::SetNextWindowPos(ImVec2(10, 10), ImGuiCond_FirstUseEver);
+    ImGui::SetNextWindowSize(ImVec2(500, 250), ImGuiCond_FirstUseEver);
+    ImGui::Begin("Test");
+    ImGui::SliderInt("Inner", &d.tessInner, 0, 20);
+    ImGui::SliderInt("Outer", &d.tessOuter, 0, 20);
+    ImGui::SliderFloat("Displacement", &d.displacementAmount, 0.0f, 4.0f);
+    ImGui::Checkbox("Use displacement texture", &d.useTex);
+    ImGui::SliderFloat("Z", &d.viewZ, -16.0f, 4.0f);
+    ImGui::Checkbox("Rotate", &d.rotate);
+    ImGui::Checkbox("Wireframe", &d.wireframe);
+    ImGui::End();
+}