Adaptable shader effect enablers

The D3D12 node implementation is mostly missing. The rest of the enablers
should be in place now however.

Importing QtQuick 2.8 provides new properties for ShaderEffect:

- shaderType can be used to decide which language should be used

- shaderCompilationType tells if compilation is runtime or offline

- shaderSourceType tells if the vertex/fragmentShader properties refer
  to source strings or source files or pre-compiled bytecode files

The last two are bitmasks. In practice however we will support only
one approach per backend for now (runtime + source string for OpenGL,
offline + bytecode for D3D12).

In addition to QSGShaderEffectNode, introduce the QSGGuiThreadShaderEffectManager
interface. This provides the gui thread bits for the above and performs shader
reflection. Backends that use the new ShaderEffect system must provide both.
For each ShaderEffect item there will be a manager (on the gui thread) and
a node (on the render thread).

Reflection is expected to be done via standard helper libs (d3d12shader
+ D3DReflect from d3dcompiler for the D3D12 backend), or via manually inspecting
SPIR-V, or parsing the source (like the GL path does now), or by using some
3rd party library (not recommended). In any case we require that reflection is
doable on the gui thread without dependencies to the actual graphics API.

The ShaderEffect documentation is greatly extended, covering HLSL and the new
properties.

The test app uses manually compiled shaders on its HLSL path for now. This
is because there is no story yet for build system integration for public
use (the internal HLSL -> bytecode in C header rule is only suitable for
the d3d12 plugin itself, apps need something different).

Change-Id: Id112104906fbcb26b9902a35f19d8d509b340d1b
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

1 files changed, 92 insertions, 0 deletions

diff --git a/tests/manual/nodetypes/Effects.qml b/tests/manual/nodetypes/Effects.qml
new file mode 100644
index 0000000000..8af9a5eb95
--- /dev/null
+++ b/tests/manual/nodetypes/Effects.qml
@@ -0,0 +1,92 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the demonstration applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Use QtQuick 2.8 to get shaderType and the other new properties
+import QtQuick 2.8
+
+Item {
+    Rectangle {
+        color: "gray"
+        anchors.margins: 10
+        anchors.fill: parent
+        Image {
+            id: image
+            source: "qrc:/qt.png"
+        }
+        ShaderEffectSource {
+            id: effectSource
+            sourceItem: image
+            hideSource: true
+        }
+        ShaderEffect {
+            width: image.width
+            height: image.height
+            anchors.centerIn: parent
+
+            property variant source: effectSource
+            property real amplitude: 0.04 * 0.2
+            property real frequency: 20
+            property real time: 0
+
+            NumberAnimation on time { loops: Animation.Infinite; from: 0; to: Math.PI * 2; duration: 600 }
+
+            property string glslFragmentShader:
+                "uniform sampler2D source;" +
+                "uniform highp float amplitude;" +
+                "uniform highp float frequency;" +
+                "uniform highp float time;" +
+                "uniform lowp float qt_Opacity;" +
+                "varying highp vec2 qt_TexCoord0;" +
+                "void main() {" +
+                "    highp vec2 p = sin(time + frequency * qt_TexCoord0);" +
+                "    gl_FragColor = texture2D(source, qt_TexCoord0 + amplitude * vec2(p.y, -p.x)) * qt_Opacity;" +
+                "}"
+
+            property string hlslVertexShaderByteCode: "qrc:/vs_wobble.cso"
+            property string hlslPixelShaderByteCode: "qrc:/ps_wobble.cso"
+
+            // This effect does not need a custom vertex shader but have one with HLSL just to test that path as well.
+            vertexShader: shaderType === ShaderEffect.GLSL ? ""
+                                                           : (shaderType === ShaderEffect.HLSL ? hlslVertexShaderByteCode : "")
+            fragmentShader: shaderType === ShaderEffect.GLSL ? glslFragmentShader
+                                                             : (shaderType === ShaderEffect.HLSL ? hlslPixelShaderByteCode : "")
+        }
+    }
+}