rhi: Add support for polygon fill mode

Support for Polygon Mode (Triangle Fill Mode in Metal, Fill Mode in D3D)
in the RHI graphics pipeline.

Options are Fill and Line

Status:
    OpenGL - ok
    Vulkan - ok
    Metal - ok
    D3D11 - ok
    OpenGL ES - does not support glPolygonMode.

Change-Id: I20b7ef416624700c3dc8d1cbe6474f4ca3889db8
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

9 files changed, 194 insertions, 0 deletions

diff --git a/tests/manual/rhi/CMakeLists.txt b/tests/manual/rhi/CMakeLists.txt
index 5b756dbee3..b3bb4581c3 100644
--- a/tests/manual/rhi/CMakeLists.txt
+++ b/tests/manual/rhi/CMakeLists.txt
@@ -23,4 +23,5 @@ add_subdirectory(instancing)
 add_subdirectory(noninstanced)
 add_subdirectory(tex3d)
 add_subdirectory(texturearray)
+add_subdirectory(polygonmode)
 add_subdirectory(tessellation)
diff --git a/tests/manual/rhi/polygonmode/CMakeLists.txt b/tests/manual/rhi/polygonmode/CMakeLists.txt
new file mode 100644
index 0000000000..ff2125d3a7
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/CMakeLists.txt
@@ -0,0 +1,20 @@
+qt_internal_add_manual_test(polygonmode
+    GUI
+    SOURCES
+        polygonmode.cpp
+    PUBLIC_LIBRARIES
+        Qt::Gui
+        Qt::GuiPrivate
+)
+
+set(polygonmode_resource_files
+    "test.vert.qsb"
+    "test.frag.qsb"
+)
+
+qt_internal_add_resource(polygonmode "polygonmode"
+    PREFIX
+        "/"
+    FILES
+        ${polygonmode_resource_files}
+)
diff --git a/tests/manual/rhi/polygonmode/buildshaders.bat b/tests/manual/rhi/polygonmode/buildshaders.bat
new file mode 100755
index 0000000000..3cd87ed7a2
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/buildshaders.bat
@@ -0,0 +1,2 @@
+qsb --glsl 320es,410,120 test.vert --msl 12 --hlsl 50 -o test.vert.qsb
+qsb --glsl 320es,410,120 test.frag --msl 12 --hlsl 50 -o test.frag.qsb
diff --git a/tests/manual/rhi/polygonmode/polygonmode.cpp b/tests/manual/rhi/polygonmode/polygonmode.cpp
new file mode 100644
index 0000000000..0fbca228a0
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/polygonmode.cpp
@@ -0,0 +1,148 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 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 "../shared/examplefw.h"
+
+static const float geom[] = {
+    -0.5f, 0.5f, 0.0f,   1.0f, 0.0f, 0.0f,
+    -0.5f, -0.5f, 0.0f,  0.0f, 1.0f, 0.0f,
+    0.0f, 0.5f, 0.0f,    0.0f, 0.0f, 1.0f,
+    0.0f, -0.5f, 0.0f,   1.0f, 0.0f, 1.0f,
+    0.5f, 0.5f, 0.0f,    1.0f, 1.0f, 0.0f,
+    0.5f, -0.5f, 0.0f,   0.0f, 1.0f, 1.0f,
+
+};
+
+struct {
+    QVector<QRhiResource *> releasePool;
+    QRhiBuffer *vbuf = nullptr;
+    QRhiShaderResourceBindings *srb = nullptr;
+    QRhiGraphicsPipeline *ps = nullptr;
+    QRhiResourceUpdateBatch *initialUpdates = nullptr;
+    int count = 0;
+} d;
+
+void Window::customInit()
+{
+    m_clearColor = QColor("black");
+
+    d.vbuf = m_r->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(geom));
+    d.vbuf->create();
+    d.releasePool << d.vbuf;
+
+    d.srb = m_r->newShaderResourceBindings();
+    d.releasePool << d.srb;
+    d.srb->create();
+
+    d.ps = m_r->newGraphicsPipeline();
+    d.releasePool << d.ps;
+
+    d.ps->setTopology(QRhiGraphicsPipeline::TriangleStrip);
+
+    d.ps->setShaderStages({
+        { QRhiShaderStage::Vertex, getShader(QLatin1String(":/test.vert.qsb")) },
+        { QRhiShaderStage::Fragment, getShader(QLatin1String(":/test.frag.qsb")) }
+    });
+
+    d.ps->setCullMode(QRhiGraphicsPipeline::None);
+    d.ps->setPolygonMode(QRhiGraphicsPipeline::Line);
+    d.ps->setDepthTest(true);
+    d.ps->setDepthWrite(true);
+    QRhiVertexInputLayout inputLayout;
+    inputLayout.setBindings({
+        { 6 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float3, 0 },
+        { 0, 1, QRhiVertexInputAttribute::Float3, 3 * 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, geom);
+}
+
+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 = m_r->nextResourceUpdateBatch();
+    if (d.initialUpdates) {
+        u->merge(d.initialUpdates);
+        d.initialUpdates->release();
+        d.initialUpdates = nullptr;
+    }
+
+    QRhiGraphicsPipeline::PolygonMode polygonMode =
+            (++d.count / 60) % 2 ? QRhiGraphicsPipeline::Fill : QRhiGraphicsPipeline::Line;
+
+    if (d.ps->polygonMode() != polygonMode) {
+        d.ps->setPolygonMode(polygonMode);
+        d.ps->create();
+    }
+
+    cb->beginPass(m_sc->currentFrameRenderTarget(), m_clearColor, { 1.0f, 0 }, u);
+    cb->setGraphicsPipeline(d.ps);
+    cb->setViewport({ 0, 0, float(outputSizeInPixels.width()), float(outputSizeInPixels.height()) });
+    cb->setShaderResources();
+    QRhiCommandBuffer::VertexInput vbufBinding(d.vbuf, 0);
+    cb->setVertexInput(0, 1, &vbufBinding);
+    cb->draw(6);
+    cb->endPass();
+}
diff --git a/tests/manual/rhi/polygonmode/test.frag b/tests/manual/rhi/polygonmode/test.frag
new file mode 100644
index 0000000000..375587662f
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/test.frag
@@ -0,0 +1,10 @@
+#version 440
+
+layout(location = 0) in vec3 v_color;
+
+layout(location = 0) out vec4 fragColor;
+
+void main()
+{
+    fragColor = vec4(v_color, 1.0);
+}
diff --git a/tests/manual/rhi/polygonmode/test.frag.qsb b/tests/manual/rhi/polygonmode/test.frag.qsb
new file mode 100644
index 0000000000..4c52be820b
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/test.frag.qsb
diff --git a/tests/manual/rhi/polygonmode/test.vert b/tests/manual/rhi/polygonmode/test.vert
new file mode 100644
index 0000000000..3838d2f3bb
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/test.vert
@@ -0,0 +1,12 @@
+#version 440
+
+layout(location = 0) in vec3 position;
+layout(location = 1) in vec3 color;
+
+layout(location = 0) out vec3 v_color;
+
+void main()
+{
+    gl_Position = vec4(position, 1.0);
+    v_color = color;
+}
diff --git a/tests/manual/rhi/polygonmode/test.vert.qsb b/tests/manual/rhi/polygonmode/test.vert.qsb
new file mode 100644
index 0000000000..de4e434354
--- /dev/null
+++ b/tests/manual/rhi/polygonmode/test.vert.qsb
diff --git a/tests/manual/rhi/tessellation/tessellation.cpp b/tests/manual/rhi/tessellation/tessellation.cpp
index e8a031a1cf..f92671b0e9 100644
--- a/tests/manual/rhi/tessellation/tessellation.cpp
+++ b/tests/manual/rhi/tessellation/tessellation.cpp
@@ -100,6 +100,7 @@ void Window::customInit()
     });
 
     d.ps->setCullMode(QRhiGraphicsPipeline::Back);
+    d.ps->setPolygonMode(QRhiGraphicsPipeline::Line);
     d.ps->setDepthTest(true);
     d.ps->setDepthWrite(true);
     QRhiVertexInputLayout inputLayout;