qt6windows7/tests/manual/rhi/shadowmap/shadowmap.cpp
2023-10-29 23:33:08 +01:00

258 lines
9.7 KiB
C++

// Copyright (C) 2018 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "../shared/examplefw.h"
#include "../shared/cube.h"
// Depth texture / shadow sampler / shadow map example.
// Not available on GLES 2.0.
static float quadVertexData[] =
{ // Y up, CCW, x-y-z
-0.5f, 0.5f, 0.0f,
-0.5f, -0.5f, 0.0f,
0.5f, -0.5f, 0.0f,
0.5f, 0.5f, 0.0f,
};
static quint16 quadIndexData[] =
{
0, 1, 2, 0, 2, 3
};
struct {
QList<QRhiResource *> releasePool;
QRhiBuffer *vbuf = nullptr;
QRhiBuffer *ibuf = nullptr;
QRhiBuffer *ubuf = nullptr;
QRhiSampler *shadowSampler = nullptr;
QRhiShaderResourceBindings *srb = nullptr;
QRhiGraphicsPipeline *ps = nullptr;
QRhiResourceUpdateBatch *initialUpdates = nullptr;
QMatrix4x4 winProj;
float cubeRot = 0;
QRhiTextureRenderTarget *rt = nullptr;
QRhiRenderPassDescriptor *rtRp = nullptr;
QRhiTexture *shadowMap = nullptr;
QRhiShaderResourceBindings *shadowSrb = nullptr;
QRhiGraphicsPipeline *shadowPs = nullptr;
} d;
const int UBLOCK_SIZE = 64 * 3 + 4;
const int SHADOW_UBLOCK_SIZE = 64 * 1;
const int UBUF_SLOTS = 4; // 2 objects * 2 passes with different cameras
void Window::customInit()
{
if (!m_r->isTextureFormatSupported(QRhiTexture::D32F))
qFatal("Depth texture is not supported");
d.vbuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(quadVertexData) + sizeof(cube));
d.vbuf->create();
d.releasePool << d.vbuf;
d.ibuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::IndexBuffer, sizeof(quadIndexData));
d.ibuf->create();
d.releasePool << d.ibuf;
const int oneRoundedUniformBlockSize = m_r->ubufAligned(UBLOCK_SIZE);
d.ubuf = m_r->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, UBUF_SLOTS * oneRoundedUniformBlockSize);
d.ubuf->create();
d.releasePool << d.ubuf;
d.shadowMap = m_r->newTexture(QRhiTexture::D32F, QSize(1024, 1024), 1, QRhiTexture::RenderTarget);
d.releasePool << d.shadowMap;
d.shadowMap->create();
d.shadowSampler = m_r->newSampler(QRhiSampler::Nearest, QRhiSampler::Nearest, QRhiSampler::None,
QRhiSampler::ClampToEdge, QRhiSampler::ClampToEdge);
d.releasePool << d.shadowSampler;
d.shadowSampler->setTextureCompareOp(QRhiSampler::Less);
d.shadowSampler->create();
d.srb = m_r->newShaderResourceBindings();
d.releasePool << d.srb;
const QRhiShaderResourceBinding::StageFlags stages = QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage;
d.srb->setBindings({ QRhiShaderResourceBinding::uniformBufferWithDynamicOffset(0, stages, d.ubuf, UBLOCK_SIZE),
QRhiShaderResourceBinding::sampledTexture(1, QRhiShaderResourceBinding::FragmentStage, d.shadowMap, d.shadowSampler) });
d.srb->create();
d.ps = m_r->newGraphicsPipeline();
d.releasePool << d.ps;
d.ps->setShaderStages({
{ QRhiShaderStage::Vertex, getShader(QLatin1String(":/main.vert.qsb")) },
{ QRhiShaderStage::Fragment, getShader(QLatin1String(":/main.frag.qsb")) }
});
d.ps->setDepthTest(true);
d.ps->setDepthWrite(true);
// fits both the quad and cube vertex data
QRhiVertexInputLayout inputLayout;
inputLayout.setBindings({
{ 3 * sizeof(float) }
});
inputLayout.setAttributes({
{ 0, 0, QRhiVertexInputAttribute::Float3, 0 },
});
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(quadVertexData), quadVertexData);
d.initialUpdates->uploadStaticBuffer(d.vbuf, sizeof(quadVertexData), sizeof(cube), cube);
d.initialUpdates->uploadStaticBuffer(d.ibuf, quadIndexData);
QRhiTextureRenderTargetDescription rtDesc;
rtDesc.setDepthTexture(d.shadowMap);
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.shadowSrb = m_r->newShaderResourceBindings();
d.releasePool << d.shadowSrb;
d.shadowSrb->setBindings({ QRhiShaderResourceBinding::uniformBufferWithDynamicOffset(0, stages, d.ubuf, SHADOW_UBLOCK_SIZE) });
d.shadowSrb->create();
d.shadowPs = m_r->newGraphicsPipeline();
d.releasePool << d.shadowPs;
d.shadowPs->setShaderStages({
{ QRhiShaderStage::Vertex, getShader(QLatin1String(":/shadowmap.vert.qsb")) },
{ QRhiShaderStage::Fragment, getShader(QLatin1String(":/shadowmap.frag.qsb")) }
});
d.shadowPs->setDepthTest(true);
d.shadowPs->setDepthWrite(true);
inputLayout.setBindings({
{ 3 * sizeof(float) }
});
inputLayout.setAttributes({
{ 0, 0, QRhiVertexInputAttribute::Float3, 0 }
});
d.shadowPs->setVertexInputLayout(inputLayout);
d.shadowPs->setShaderResourceBindings(d.shadowSrb);
d.shadowPs->setRenderPassDescriptor(d.rtRp);
d.shadowPs->create();
}
void Window::customRelease()
{
qDeleteAll(d.releasePool);
d.releasePool.clear();
}
static void enqueueScene(QRhiCommandBuffer *cb, QRhiShaderResourceBindings *srb, int oneRoundedUniformBlockSize, int firstUbufSlot)
{
QRhiCommandBuffer::DynamicOffset ubufOffset(0, quint32(firstUbufSlot * oneRoundedUniformBlockSize));
// draw the ground (the quad)
cb->setShaderResources(srb, 1, &ubufOffset);
QRhiCommandBuffer::VertexInput vbufBinding(d.vbuf, 0);
cb->setVertexInput(0, 1, &vbufBinding, d.ibuf, 0, QRhiCommandBuffer::IndexUInt16);
cb->drawIndexed(6);
// Draw the object (the cube). Both vertex and uniform data are in the same
// buffer, right after the quad's.
ubufOffset.second += oneRoundedUniformBlockSize;
cb->setShaderResources(srb, 1, &ubufOffset);
vbufBinding.second = sizeof(quadVertexData);
cb->setVertexInput(0, 1, &vbufBinding);
cb->draw(36);
}
void Window::customRender()
{
const QSize outputSizeInPixels = m_sc->currentPixelSize();
QRhiCommandBuffer *cb = m_sc->currentFrameCommandBuffer();
QRhiResourceUpdateBatch *u = m_r->nextResourceUpdateBatch();
if (d.initialUpdates) {
u->merge(d.initialUpdates);
d.initialUpdates->release();
d.initialUpdates = nullptr;
}
const int oneRoundedUniformBlockSize = m_r->ubufAligned(UBLOCK_SIZE);
QMatrix4x4 shadowBias;
// fill it in column-major order to keep our sanity (ctor would take row-major)
float *sbp = shadowBias.data();
if (m_r->isClipDepthZeroToOne()) {
// convert x, y [-1, 1] -> [0, 1]
*sbp++ = 0.5f; *sbp++ = 0.0f; *sbp++ = 0.0f; *sbp++ = 0.0f;
*sbp++ = 0.0f; *sbp++ = m_r->isYUpInNDC() ? -0.5f : 0.5f; *sbp++ = 0.0f; *sbp++ = 0.0f;
*sbp++ = 0.0f; *sbp++ = 0.0f; *sbp++ = 1.0f; *sbp++ = 0.0f;
*sbp++ = 0.5f; *sbp++ = 0.5f; *sbp++ = 0.0f; *sbp++ = 1.0f;
} else {
// convert x, y, z [-1, 1] -> [0, 1]
*sbp++ = 0.5f; *sbp++ = 0.0f; *sbp++ = 0.0f; *sbp++ = 0.0f;
*sbp++ = 0.0f; *sbp++ = 0.5f; *sbp++ = 0.0f; *sbp++ = 0.0f;
*sbp++ = 0.0f; *sbp++ = 0.0f; *sbp++ = 0.5f; *sbp++ = 0.0f;
*sbp++ = 0.5f; *sbp++ = 0.5f; *sbp++ = 0.5f; *sbp++ = 1.0f;
}
const QVector3D lightPos(5, 10, 10);
QMatrix4x4 lightViewProj = m_r->clipSpaceCorrMatrix();
lightViewProj.perspective(45.0f, 1, 0.1f, 100.0f);
lightViewProj.lookAt(lightPos, QVector3D(0, 0, 0), QVector3D(0, 1, 0));
// uniform data for the ground
if (d.winProj != m_proj) {
d.winProj = m_proj;
QMatrix4x4 m;
m.scale(4.0f);
m.rotate(-60, 1, 0, 0);
// for the main pass
const QMatrix4x4 mvp = m_proj * m; // m_proj is in fact projection * view
u->updateDynamicBuffer(d.ubuf, 0, 64, mvp.constData());
const QMatrix4x4 shadowMvp = lightViewProj * m;
u->updateDynamicBuffer(d.ubuf, 64, 64, shadowMvp.constData());
u->updateDynamicBuffer(d.ubuf, 128, 64, shadowBias.constData());
qint32 useShadows = 1;
u->updateDynamicBuffer(d.ubuf, 192, 4, &useShadows);
// for the shadow pass
u->updateDynamicBuffer(d.ubuf, 2 * oneRoundedUniformBlockSize, 64, shadowMvp.constData());
}
// uniform data for the rotating cube
QMatrix4x4 m;
m.translate(0, 0.5f, 2);
m.scale(0.2f);
m.rotate(d.cubeRot, 0, 1, 0);
m.rotate(45, 1, 0, 0);
d.cubeRot += 1;
// for the main pass
const QMatrix4x4 mvp = m_proj * m;
u->updateDynamicBuffer(d.ubuf, oneRoundedUniformBlockSize, 64, mvp.constData());
const QMatrix4x4 shadowMvp = lightViewProj * m;
u->updateDynamicBuffer(d.ubuf, oneRoundedUniformBlockSize + 64, 64, shadowMvp.constData());
u->updateDynamicBuffer(d.ubuf, oneRoundedUniformBlockSize + 128, 64, shadowBias.constData());
qint32 useShadows = 0;
u->updateDynamicBuffer(d.ubuf, oneRoundedUniformBlockSize + 192, 4, &useShadows);
// for the shadow pass
u->updateDynamicBuffer(d.ubuf, 3 * oneRoundedUniformBlockSize, 64, shadowMvp.constData());
cb->resourceUpdate(u);
// shadow pass
const QSize shadowMapSize = d.shadowMap->pixelSize();
cb->beginPass(d.rt, QColor(), { 1.0f, 0 });
cb->setGraphicsPipeline(d.shadowPs);
cb->setViewport({ 0, 0, float(shadowMapSize.width()), float(shadowMapSize.height()) });
enqueueScene(cb, d.shadowSrb, oneRoundedUniformBlockSize, 2);
cb->endPass();
// main pass
cb->beginPass(m_sc->currentFrameRenderTarget(), m_clearColor, { 1.0f, 0 });
cb->setGraphicsPipeline(d.ps);
cb->setViewport({ 0, 0, float(outputSizeInPixels.width()), float(outputSizeInPixels.height()) });
enqueueScene(cb, d.srb, oneRoundedUniformBlockSize, 0);
cb->endPass();
}