1 files changed, 235 insertions, 0 deletions
diff --git a/tests/manual/rhi/msaatextureresolve/msaatextureresolve.cpp b/tests/manual/rhi/msaatextureresolve/msaatextureresolve.cpp
new file mode 100644
index 0000000000..128cecf707
--- /dev/null
+++ b/tests/manual/rhi/msaatextureresolve/msaatextureresolve.cpp
@@ -0,0 +1,235 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#include "../shared/examplefw.h"
+
+// Uses a multisample texture both for color and depth-stencil, renders into
+// those, and then resolves into non-multisample textures. Also the
+// depth-stencil, in order to exercise that rarely used path. If that is
+// functional, will not be visible on-screen. Frame captures with tools such as
+// RenderDoc can be used to verify that there is indeed a non-multisample depth
+// texture generated.
+
+static float vertexData[] =
+{ // Y up, CCW
+  -0.5f,   0.5f,   0.0f, 0.0f,
+  -0.5f,  -0.5f,   0.0f, 1.0f,
+  0.5f,   -0.5f,   1.0f, 1.0f,
+  0.5f,   0.5f,    1.0f, 0.0f
+};
+
+static quint16 indexData[] =
+{
+    0, 1, 2, 0, 2, 3
+};
+
+static float triangleData[] =
+{ // Y up, CCW
+     0.0f,   0.5f,   1.0f, 0.0f, 0.0f,
+    -0.5f,  -0.5f,   0.0f, 1.0f, 0.0f,
+     0.5f,  -0.5f,   0.0f, 0.0f, 1.0f,
+};
+
+struct {
+    QList<QRhiResource *> releasePool;
+    QRhiBuffer *vbuf = nullptr;
+    QRhiBuffer *ibuf = nullptr;
+    QRhiBuffer *ubuf = nullptr;
+    QRhiTexture *msaaColorTexture = nullptr;
+    QRhiTexture *msaaDepthTexture = nullptr;
+    QRhiTextureRenderTarget *rt = nullptr;
+    QRhiRenderPassDescriptor *rtRp = nullptr;
+    QRhiTexture *tex = nullptr;
+    QRhiTexture *depthTex = nullptr;
+    QRhiSampler *sampler = nullptr;
+    QRhiBuffer *triUbuf = nullptr;
+    QRhiShaderResourceBindings *triSrb = nullptr;
+    QRhiGraphicsPipeline *triPs = nullptr;
+    QRhiShaderResourceBindings *srb = nullptr;
+    QRhiGraphicsPipeline *ps = nullptr;
+    QRhiResourceUpdateBatch *initialUpdates = nullptr;
+    QMatrix4x4 triBaseMvp;
+    float triRot = 0;
+    QMatrix4x4 winProj;
+} d;
+
+void Window::customInit()
+{
+    if (!m_r->isFeatureSupported(QRhi::MultisampleTexture))
+        qFatal("Multisample textures not supported by this backend");
+
+    // Skip the check for ResolveDepthStencil, and let it run regardless. When
+    // not supported, it won't be functional, but should be handled somewhat
+    // gracefully.
+
+    d.vbuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(vertexData) + sizeof(triangleData));
+    d.vbuf->create();
+    d.releasePool << d.vbuf;
+
+    d.ibuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::IndexBuffer, sizeof(indexData));
+    d.ibuf->create();
+    d.releasePool << d.ibuf;
+
+    d.ubuf = m_r->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, 68);
+    d.ubuf->create();
+    d.releasePool << d.ubuf;
+
+    d.msaaColorTexture = m_r->newTexture(QRhiTexture::RGBA8, QSize(512, 512), 4, QRhiTexture::RenderTarget); // 4x MSAA
+    d.msaaColorTexture->create();
+    d.releasePool << d.msaaColorTexture;
+
+    d.msaaDepthTexture = m_r->newTexture(QRhiTexture::D24S8, QSize(512, 512), 4, QRhiTexture::RenderTarget); // 4x MSAA
+    d.msaaDepthTexture->create();
+    d.releasePool << d.msaaDepthTexture;
+
+    // the non-msaa texture that will be the destination in the resolve
+    d.tex = m_r->newTexture(QRhiTexture::RGBA8, d.msaaColorTexture->pixelSize(), 1, QRhiTexture::RenderTarget);
+    d.releasePool << d.tex;
+    d.tex->create();
+
+    d.depthTex = m_r->newTexture(QRhiTexture::D24S8, d.msaaDepthTexture->pixelSize(), 1, QRhiTexture::RenderTarget);
+    d.releasePool << d.depthTex;
+    d.depthTex->create();
+
+    QRhiTextureRenderTargetDescription rtDesc;
+    QRhiColorAttachment rtAtt(d.msaaColorTexture);
+    rtAtt.setResolveTexture(d.tex);
+    rtDesc.setColorAttachments({ rtAtt });
+    rtDesc.setDepthTexture(d.msaaDepthTexture);
+    rtDesc.setDepthResolveTexture(d.depthTex);
+
+    d.rt = m_r->newTextureRenderTarget(rtDesc);
+    d.releasePool << d.rt;
+    d.rtRp = d.rt->newCompatibleRenderPassDescriptor();
+    d.releasePool << d.rtRp;
+    d.rt->setRenderPassDescriptor(d.rtRp);
+    d.rt->create();
+
+    d.triUbuf = m_r->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, 68);
+    d.releasePool << d.triUbuf;
+    d.triUbuf->create();
+
+    d.triSrb = m_r->newShaderResourceBindings();
+    d.releasePool << d.triSrb;
+    d.triSrb->setBindings({
+        QRhiShaderResourceBinding::uniformBuffer(0, QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage, d.triUbuf)
+    });
+    d.triSrb->create();
+
+    d.triPs = m_r->newGraphicsPipeline();
+    d.releasePool << d.triPs;
+    d.triPs->setDepthTest(true);
+    d.triPs->setDepthWrite(true);
+    d.triPs->setSampleCount(4); // must match the render target
+    d.triPs->setShaderStages({
+        { QRhiShaderStage::Vertex, getShader(QLatin1String(":/color.vert.qsb")) },
+        { QRhiShaderStage::Fragment, getShader(QLatin1String(":/color.frag.qsb")) }
+    });
+    QRhiVertexInputLayout inputLayout;
+    inputLayout.setBindings({
+        { 5 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float2, 0 },
+        { 0, 1, QRhiVertexInputAttribute::Float3, quint32(2 * sizeof(float)) }
+    });
+    d.triPs->setVertexInputLayout(inputLayout);
+    d.triPs->setShaderResourceBindings(d.triSrb);
+    d.triPs->setRenderPassDescriptor(d.rtRp);
+    d.triPs->create();
+
+    d.sampler = m_r->newSampler(QRhiSampler::Linear, QRhiSampler::Linear, QRhiSampler::None,
+                                QRhiSampler::ClampToEdge, QRhiSampler::ClampToEdge);
+    d.releasePool << d.sampler;
+    d.sampler->create();
+
+    d.srb = m_r->newShaderResourceBindings();
+    d.releasePool << d.srb;
+    d.srb->setBindings({
+        QRhiShaderResourceBinding::uniformBuffer(0, QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage, d.ubuf),
+        QRhiShaderResourceBinding::sampledTexture(1, QRhiShaderResourceBinding::FragmentStage, d.tex, d.sampler)
+    });
+    d.srb->create();
+
+    d.ps = m_r->newGraphicsPipeline();
+    d.releasePool << d.ps;
+    d.ps->setShaderStages({
+        { QRhiShaderStage::Vertex, getShader(QLatin1String(":/texture.vert.qsb")) },
+        { QRhiShaderStage::Fragment, getShader(QLatin1String(":/texture.frag.qsb")) }
+    });
+    inputLayout.setBindings({
+        { 4 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float2, 0 },
+        { 0, 1, QRhiVertexInputAttribute::Float2, quint32(2 * sizeof(float)) }
+    });
+    d.ps->setVertexInputLayout(inputLayout);
+    d.ps->setShaderResourceBindings(d.srb);
+    d.ps->setRenderPassDescriptor(m_rp);
+    d.ps->create();
+
+    d.initialUpdates = m_r->nextResourceUpdateBatch();
+    d.initialUpdates->uploadStaticBuffer(d.vbuf, 0, sizeof(vertexData), vertexData);
+    d.initialUpdates->uploadStaticBuffer(d.vbuf, sizeof(vertexData), sizeof(triangleData), triangleData);
+    d.initialUpdates->uploadStaticBuffer(d.ibuf, indexData);
+
+    d.triBaseMvp = m_r->clipSpaceCorrMatrix();
+    d.triBaseMvp.perspective(45.0f, d.msaaColorTexture->pixelSize().width() / float(d.msaaColorTexture->pixelSize().height()), 0.01f, 1000.0f);
+    d.triBaseMvp.translate(0, 0, -2);
+    float opacity = 1.0f;
+    d.initialUpdates->updateDynamicBuffer(d.triUbuf, 64, 4, &opacity);
+
+    qint32 flip = m_r->isYUpInFramebuffer() ? 1 : 0;
+    d.initialUpdates->updateDynamicBuffer(d.ubuf, 64, 4, &flip);
+}
+
+void Window::customRelease()
+{
+    qDeleteAll(d.releasePool);
+    d.releasePool.clear();
+}
+
+void Window::customRender()
+{
+    QRhiCommandBuffer *cb = m_sc->currentFrameCommandBuffer();
+    QRhiResourceUpdateBatch *u = m_r->nextResourceUpdateBatch();
+    if (d.initialUpdates) {
+        u->merge(d.initialUpdates);
+        d.initialUpdates->release();
+        d.initialUpdates = nullptr;
+    }
+
+    QMatrix4x4 triMvp = d.triBaseMvp;
+    triMvp.rotate(d.triRot, 0, 1, 0);
+    d.triRot += 1;
+    u->updateDynamicBuffer(d.triUbuf, 0, 64, triMvp.constData());
+
+    if (d.winProj != m_proj) {
+        d.winProj = m_proj;
+        QMatrix4x4 mvp = m_proj;
+        mvp.scale(2.5f);
+        u->updateDynamicBuffer(d.ubuf, 0, 64, mvp.constData());
+    }
+
+    // offscreen (triangle, msaa)
+    cb->beginPass(d.rt, QColor::fromRgbF(0.5f, 0.2f, 0.0f, 1.0f), { 1.0f, 0 }, u);
+    cb->setGraphicsPipeline(d.triPs);
+    cb->setViewport({ 0, 0, float(d.msaaColorTexture->pixelSize().width()), float(d.msaaColorTexture->pixelSize().height()) });
+    cb->setShaderResources();
+    QRhiCommandBuffer::VertexInput vbufBinding(d.vbuf, quint32(sizeof(vertexData)));
+    cb->setVertexInput(0, 1, &vbufBinding);
+    cb->draw(3);
+    cb->endPass();
+
+    // onscreen (quad)
+    const QSize outputSizeInPixels = m_sc->currentPixelSize();
+    cb->beginPass(m_sc->currentFrameRenderTarget(), m_clearColor, { 1.0f, 0 });
+    cb->setGraphicsPipeline(d.ps);
+    cb->setViewport({ 0, 0, float(outputSizeInPixels.width()), float(outputSizeInPixels.height()) });
+    cb->setShaderResources();
+    vbufBinding.second = 0;
+    cb->setVertexInput(0, 1, &vbufBinding, d.ibuf, 0, QRhiCommandBuffer::IndexUInt16);
+    cb->drawIndexed(6);
+    cb->endPass();
+}