Introduce the Qt graphics abstraction as private QtGui helpers

Comes with backends for Vulkan, Metal, Direct3D 11.1, and OpenGL (ES).

All APIs are private for now.

Shader conditioning (i.e. generating a QRhiShader in memory or on disk
from some shader source code) is done via the tools and APIs provided
by qt-labs/qtshadertools.

The OpenGL support follows the cross-platform tradition of requiring
ES 2.0 only, while optionally using some (ES) 3.x features. It can
operate in core profile contexts as well.

Task-number: QTBUG-70287
Change-Id: I246f2e36d562e404012c05db2aa72487108aa7cc
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
 
 
 
 
 

1 files changed, 292 insertions, 0 deletions

diff --git a/tests/manual/rhi/triquadcube/triangleoncuberenderer.cpp b/tests/manual/rhi/triquadcube/triangleoncuberenderer.cpp
new file mode 100644
index 0000000000..40d9615aa1
--- /dev/null
+++ b/tests/manual/rhi/triquadcube/triangleoncuberenderer.cpp
@@ -0,0 +1,292 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "triangleoncuberenderer.h"
+#include <QFile>
+#include <QtGui/private/qshader_p.h>
+
+// toggle to test the preserved content (no clear) path
+const bool IMAGE_UNDER_OFFSCREEN_RENDERING = false;
+const bool UPLOAD_UNDERLAY_ON_EVERY_FRAME = false;
+
+const bool DS_ATT = false; // have a depth-stencil attachment for the offscreen pass
+
+const bool DEPTH_TEXTURE = false; // offscreen pass uses a depth texture (verify with renderdoc etc., ignore valid.layer about ps slot 0)
+const bool MRT = false; // two textures, the second is just cleared as the shader does not write anything (valid.layer may warn but for testing that's ok)
+
+#include "../shared/cube.h"
+
+static QShader getShader(const QString &name)
+{
+    QFile f(name);
+    if (f.open(QIODevice::ReadOnly))
+        return QShader::fromSerialized(f.readAll());
+
+    return QShader();
+}
+
+static const QSize OFFSCREEN_SIZE(512, 512);
+
+void TriangleOnCubeRenderer::initResources(QRhiRenderPassDescriptor *rp)
+{
+    m_vbuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(cube));
+    m_vbuf->setName(QByteArrayLiteral("Cube vbuf (textured with offscreen)"));
+    m_vbuf->build();
+    m_vbufReady = false;
+
+    m_ubuf = m_r->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, 64 + 4);
+    m_ubuf->setName(QByteArrayLiteral("Cube ubuf (textured with offscreen)"));
+    m_ubuf->build();
+
+    if (IMAGE_UNDER_OFFSCREEN_RENDERING) {
+        m_image = QImage(QLatin1String(":/qt256.png")).scaled(OFFSCREEN_SIZE).convertToFormat(QImage::Format_RGBA8888);
+        if (m_r->isYUpInFramebuffer())
+            m_image = m_image.mirrored(); // just cause we'll flip texcoord Y when y up so accommodate our static background image as well
+    }
+
+    m_tex = m_r->newTexture(QRhiTexture::RGBA8, OFFSCREEN_SIZE, 1, QRhiTexture::RenderTarget);
+    m_tex->setName(QByteArrayLiteral("Texture for offscreen content"));
+    m_tex->build();
+
+    if (MRT) {
+        m_tex2 = m_r->newTexture(QRhiTexture::RGBA8, OFFSCREEN_SIZE, 1, QRhiTexture::RenderTarget);
+        m_tex2->build();
+    }
+
+    if (DS_ATT) {
+        m_offscreenTriangle.setDepthWrite(true);
+        m_ds = m_r->newRenderBuffer(QRhiRenderBuffer::DepthStencil, m_tex->pixelSize());
+        m_ds->build();
+    }
+
+    if (DEPTH_TEXTURE) {
+        m_offscreenTriangle.setDepthWrite(true);
+        m_depthTex = m_r->newTexture(QRhiTexture::D32F, OFFSCREEN_SIZE, 1, QRhiTexture::RenderTarget);
+        m_depthTex->build();
+    }
+
+    m_sampler = m_r->newSampler(QRhiSampler::Linear, QRhiSampler::Linear, QRhiSampler::None, QRhiSampler::ClampToEdge, QRhiSampler::ClampToEdge);
+    m_sampler->build();
+
+    m_srb = m_r->newShaderResourceBindings();
+    m_srb->setBindings({
+        QRhiShaderResourceBinding::uniformBuffer(0, QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage, m_ubuf),
+        QRhiShaderResourceBinding::sampledTexture(1, QRhiShaderResourceBinding::FragmentStage, m_tex, m_sampler)
+    });
+    m_srb->build();
+
+    m_ps = m_r->newGraphicsPipeline();
+
+    m_ps->setDepthTest(true);
+    m_ps->setDepthWrite(true);
+    m_ps->setDepthOp(QRhiGraphicsPipeline::Less);
+
+    m_ps->setCullMode(QRhiGraphicsPipeline::Back);
+    m_ps->setFrontFace(QRhiGraphicsPipeline::CCW);
+
+    m_ps->setSampleCount(m_sampleCount);
+
+    QShader vs = getShader(QLatin1String(":/texture.vert.qsb"));
+    Q_ASSERT(vs.isValid());
+    QShader fs = getShader(QLatin1String(":/texture.frag.qsb"));
+    Q_ASSERT(fs.isValid());
+    m_ps->setShaderStages({
+        { QRhiGraphicsShaderStage::Vertex, vs },
+        { QRhiGraphicsShaderStage::Fragment, fs }
+    });
+
+    QRhiVertexInputLayout inputLayout;
+    inputLayout.setBindings({
+        { 3 * sizeof(float) },
+        { 2 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float3, 0 },
+        { 1, 1, QRhiVertexInputAttribute::Float2, 0 }
+    });
+
+    m_ps->setVertexInputLayout(inputLayout);
+    m_ps->setShaderResourceBindings(m_srb);
+    m_ps->setRenderPassDescriptor(rp);
+
+    m_ps->build();
+
+    QRhiTextureRenderTarget::Flags rtFlags = 0;
+    if (IMAGE_UNDER_OFFSCREEN_RENDERING)
+        rtFlags |= QRhiTextureRenderTarget::PreserveColorContents;
+
+    if (DEPTH_TEXTURE) {
+        QRhiTextureRenderTargetDescription desc;
+        desc.setDepthTexture(m_depthTex);
+        m_rt = m_r->newTextureRenderTarget(desc, rtFlags);
+    } else {
+        QRhiTextureRenderTargetDescription desc;
+        QRhiColorAttachment color0 { m_tex };
+        if (DS_ATT)
+            desc.setDepthStencilBuffer(m_ds);
+        if (MRT) {
+            m_offscreenTriangle.setColorAttCount(2);
+            QRhiColorAttachment color1 { m_tex2 };
+            desc.setColorAttachments({ color0, color1 });
+        } else {
+            desc.setColorAttachments({ color0 });
+        }
+        m_rt = m_r->newTextureRenderTarget(desc, rtFlags);
+    }
+
+    m_rp = m_rt->newCompatibleRenderPassDescriptor();
+    m_rt->setRenderPassDescriptor(m_rp);
+
+    m_rt->build();
+
+    m_offscreenTriangle.setRhi(m_r);
+    m_offscreenTriangle.initResources(m_rp);
+    m_offscreenTriangle.setScale(2);
+    // m_tex and the offscreen triangle are never multisample
+}
+
+void TriangleOnCubeRenderer::resize(const QSize &pixelSize)
+{
+    m_proj = m_r->clipSpaceCorrMatrix();
+    m_proj.perspective(45.0f, pixelSize.width() / (float) pixelSize.height(), 0.01f, 100.0f);
+    m_proj.translate(0, 0, -4);
+
+    m_offscreenTriangle.resize(pixelSize);
+}
+
+void TriangleOnCubeRenderer::releaseResources()
+{
+    m_offscreenTriangle.releaseResources();
+
+    delete m_ps;
+    m_ps = nullptr;
+
+    delete m_srb;
+    m_srb = nullptr;
+
+    delete m_rt;
+    m_rt = nullptr;
+
+    delete m_rp;
+    m_rp = nullptr;
+
+    delete m_sampler;
+    m_sampler = nullptr;
+
+    delete m_depthTex;
+    m_depthTex = nullptr;
+
+    delete m_tex2;
+    m_tex2 = nullptr;
+
+    delete m_tex;
+    m_tex = nullptr;
+
+    delete m_ds;
+    m_ds = nullptr;
+
+    delete m_ubuf;
+    m_ubuf = nullptr;
+
+    delete m_vbuf;
+    m_vbuf = nullptr;
+}
+
+void TriangleOnCubeRenderer::queueResourceUpdates(QRhiResourceUpdateBatch *resourceUpdates)
+{
+    if (!m_vbufReady) {
+        m_vbufReady = true;
+        resourceUpdates->uploadStaticBuffer(m_vbuf, cube);
+        qint32 flip = m_r->isYUpInFramebuffer() ? 1 : 0;
+        resourceUpdates->updateDynamicBuffer(m_ubuf, 64, 4, &flip);
+    }
+
+    m_rotation += 1.0f;
+    QMatrix4x4 mvp = m_proj;
+    mvp.translate(m_translation);
+    mvp.scale(0.5f);
+    mvp.rotate(m_rotation, 1, 0, 0);
+    resourceUpdates->updateDynamicBuffer(m_ubuf, 0, 64, mvp.constData());
+
+    // ###
+//    if (DEPTH_TEXTURE) {
+//        // m_tex is basically undefined here, be nice and transition the layout properly at least
+//        resourceUpdates->prepareTextureForUse(m_tex, QRhiResourceUpdateBatch::TextureRead);
+//    }
+}
+
+void TriangleOnCubeRenderer::queueOffscreenPass(QRhiCommandBuffer *cb)
+{
+    QRhiResourceUpdateBatch *u = m_r->nextResourceUpdateBatch();
+    m_offscreenTriangle.queueResourceUpdates(u);
+
+    if (IMAGE_UNDER_OFFSCREEN_RENDERING && !m_image.isNull()) {
+        u->uploadTexture(m_tex, m_image);
+        if (!UPLOAD_UNDERLAY_ON_EVERY_FRAME)
+            m_image = QImage();
+    }
+
+    cb->beginPass(m_rt, QColor::fromRgbF(0.0f, 0.4f, 0.7f, 1.0f), { 1.0f, 0 }, u);
+    m_offscreenTriangle.queueDraw(cb, OFFSCREEN_SIZE);
+    cb->endPass();
+}
+
+void TriangleOnCubeRenderer::queueDraw(QRhiCommandBuffer *cb, const QSize &outputSizeInPixels)
+{
+    cb->setGraphicsPipeline(m_ps);
+    cb->setViewport(QRhiViewport(0, 0, outputSizeInPixels.width(), outputSizeInPixels.height()));
+    cb->setShaderResources();
+    const QRhiCommandBuffer::VertexInput vbufBindings[] = {
+        { m_vbuf, 0 },
+        { m_vbuf, 36 * 3 * sizeof(float) }
+    };
+    cb->setVertexInput(0, 2, vbufBindings);
+    cb->draw(36);
+}