Enable alpha blending on QTextureMaterial

Change-Id: I8466ccd47f8bda9fec184f548a2df7807d456ac7
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

4 files changed, 63 insertions, 0 deletions

diff --git a/src/extras/defaults/qtexturematerial.cpp b/src/extras/defaults/qtexturematerial.cpp
index 6d57f3a49..5545f2018 100644
--- a/src/extras/defaults/qtexturematerial.cpp
+++ b/src/extras/defaults/qtexturematerial.cpp
@@ -48,6 +48,9 @@
 #include <Qt3DRender/qparameter.h>
 #include <Qt3DRender/qrenderpass.h>
 #include <Qt3DRender/qgraphicsapifilter.h>
+#include <Qt3DRender/qblendequation.h>
+#include <Qt3DRender/qblendequationarguments.h>
+#include <Qt3DRender/qnodepthmask.h>
 #include <QUrl>
 
 QT_BEGIN_NAMESPACE
@@ -69,6 +72,9 @@ QTextureMaterialPrivate::QTextureMaterialPrivate()
     , m_textureES2RenderPass(new QRenderPass)
     , m_textureGL3Shader(new QShaderProgram)
     , m_textureGL2ES2Shader(new QShaderProgram)
+    , m_noDepthMask(new QNoDepthMask())
+    , m_blendState(new QBlendEquationArguments())
+    , m_blendEquation(new QBlendEquation())
     , m_filterKey(new QFilterKey)
 {
 }
@@ -100,6 +106,13 @@ void QTextureMaterialPrivate::init()
     m_textureES2Technique->graphicsApiFilter()->setMinorVersion(0);
     m_textureES2Technique->graphicsApiFilter()->setProfile(QGraphicsApiFilter::NoProfile);
 
+    m_noDepthMask->setEnabled(false);
+    m_blendState->setEnabled(false);
+    m_blendState->setSourceRgb(QBlendEquationArguments::SourceAlpha);
+    m_blendState->setDestinationRgb(QBlendEquationArguments::OneMinusSourceAlpha);
+    m_blendEquation->setEnabled(false);
+    m_blendEquation->setBlendFunction(QBlendEquation::Add);
+
     Q_Q(QTextureMaterial);
     m_filterKey->setParent(q);
     m_filterKey->setName(QStringLiteral("renderingStyle"));
@@ -113,6 +126,18 @@ void QTextureMaterialPrivate::init()
     m_textureGL2RenderPass->setShaderProgram(m_textureGL2ES2Shader);
     m_textureES2RenderPass->setShaderProgram(m_textureGL2ES2Shader);
 
+    m_textureGL3RenderPass->addRenderState(m_noDepthMask);
+    m_textureGL3RenderPass->addRenderState(m_blendState);
+    m_textureGL3RenderPass->addRenderState(m_blendEquation);
+
+    m_textureGL2RenderPass->addRenderState(m_noDepthMask);
+    m_textureGL2RenderPass->addRenderState(m_blendState);
+    m_textureGL2RenderPass->addRenderState(m_blendEquation);
+
+    m_textureES2RenderPass->addRenderState(m_noDepthMask);
+    m_textureES2RenderPass->addRenderState(m_blendState);
+    m_textureES2RenderPass->addRenderState(m_blendEquation);
+
     m_textureGL3Technique->addRenderPass(m_textureGL3RenderPass);
     m_textureGL2Technique->addRenderPass(m_textureGL2RenderPass);
     m_textureES2Technique->addRenderPass(m_textureES2RenderPass);
@@ -231,6 +256,32 @@ void QTextureMaterial::setTextureTransform(const QMatrix3x3 &matrix)
     d->m_textureTransformParameter->setValue(qVariantFromValue(matrix));
 }
 
+/*!
+    \property QTextureMaterial::alphaBlending
+
+    Indicates if the alpha information coming from the diffuse property will
+    be taken into account during rendering. Defaults to false.
+*/
+/*!
+    \qmlproperty bool TextureMaterial::alphaBlending
+
+    Indicates if the alpha information coming from the diffuse property will
+    be taken into account during rendering. Defaults to false.
+*/
+bool QTextureMaterial::isAlphaBlendingEnabled() const
+{
+    Q_D(const QTextureMaterial);
+    return d->m_noDepthMask->isEnabled();
+}
+
+void QTextureMaterial::setAlphaBlendingEnabled(bool enabled)
+{
+    Q_D(QTextureMaterial);
+    d->m_noDepthMask->setEnabled(enabled);
+    d->m_blendState->setEnabled(enabled);
+    d->m_blendEquation->setEnabled(enabled);
+}
+
 } // namespace Qt3DExtras
 
 QT_END_NAMESPACE
diff --git a/src/extras/defaults/qtexturematerial.h b/src/extras/defaults/qtexturematerial.h
index c4fb43f50..4e36b1867 100644
--- a/src/extras/defaults/qtexturematerial.h
+++ b/src/extras/defaults/qtexturematerial.h
@@ -63,6 +63,8 @@ class QT3DEXTRASSHARED_EXPORT QTextureMaterial : public Qt3DRender::QMaterial
     Q_PROPERTY(Qt3DRender::QAbstractTexture *texture READ texture WRITE setTexture NOTIFY textureChanged)
     Q_PROPERTY(QVector2D textureOffset READ textureOffset WRITE setTextureOffset NOTIFY textureOffsetChanged)
     Q_PROPERTY(QMatrix3x3 textureTransform READ textureTransform WRITE setTextureTransform NOTIFY textureTransformChanged REVISION 10)
+    Q_PROPERTY(bool alphaBlending READ isAlphaBlendingEnabled WRITE setAlphaBlendingEnabled NOTIFY alphaBlendingEnabledChanged REVISION 11)
+
 public:
     explicit QTextureMaterial(Qt3DCore::QNode *parent = nullptr);
     ~QTextureMaterial();
@@ -70,16 +72,19 @@ public:
     Qt3DRender::QAbstractTexture *texture() const;
     QVector2D textureOffset() const;
     QMatrix3x3 textureTransform() const;
+    bool isAlphaBlendingEnabled() const;
 
 public Q_SLOTS:
     void setTexture(Qt3DRender::QAbstractTexture *texture);
     void setTextureOffset(QVector2D textureOffset);
     void setTextureTransform(const QMatrix3x3 &matrix);
+    void setAlphaBlendingEnabled(bool enabled);
 
 Q_SIGNALS:
     void textureChanged(Qt3DRender::QAbstractTexture *texture);
     void textureOffsetChanged(QVector2D textureOffset);
     void textureTransformChanged(const QMatrix3x3 &textureTransform);
+    void alphaBlendingEnabledChanged(bool enabled);
 
 private:
     Q_DECLARE_PRIVATE(QTextureMaterial)
diff --git a/src/extras/defaults/qtexturematerial_p.h b/src/extras/defaults/qtexturematerial_p.h
index d09458aa3..09d5e2311 100644
--- a/src/extras/defaults/qtexturematerial_p.h
+++ b/src/extras/defaults/qtexturematerial_p.h
@@ -66,6 +66,9 @@ class QTechnique;
 class QParameter;
 class QShaderProgram;
 class QRenderPass;
+class QNoDepthMask;
+class QBlendEquationArguments;
+class QBlendEquation;
 
 } // namespace Qt3DRender
 
@@ -93,6 +96,9 @@ class QTextureMaterialPrivate : public Qt3DRender::QMaterialPrivate
     Qt3DRender::QRenderPass *m_textureES2RenderPass;
     Qt3DRender::QShaderProgram *m_textureGL3Shader;
     Qt3DRender::QShaderProgram *m_textureGL2ES2Shader;
+    Qt3DRender::QNoDepthMask *m_noDepthMask;
+    Qt3DRender::QBlendEquationArguments *m_blendState;
+    Qt3DRender::QBlendEquation *m_blendEquation;
     Qt3DRender::QFilterKey *m_filterKey;
 
     Q_DECLARE_PUBLIC(QTextureMaterial)
diff --git a/src/quick3d/imports/extras/qt3dquick3dextrasplugin.cpp b/src/quick3d/imports/extras/qt3dquick3dextrasplugin.cpp
index e893696ec..9a3e76923 100644
--- a/src/quick3d/imports/extras/qt3dquick3dextrasplugin.cpp
+++ b/src/quick3d/imports/extras/qt3dquick3dextrasplugin.cpp
@@ -109,6 +109,7 @@ void Qt3DQuick3DExtrasPlugin::registerTypes(const char *uri)
     qmlRegisterType<Qt3DExtras::QGoochMaterial>(uri, 2, 0, "GoochMaterial");
     qmlRegisterType<Qt3DExtras::QTextureMaterial>(uri, 2, 0, "TextureMaterial");
     qmlRegisterRevision<Qt3DExtras::QTextureMaterial, 10>(uri, 2, 10);
+    qmlRegisterRevision<Qt3DExtras::QTextureMaterial, 11>(uri, 2, 11);
     qmlRegisterType<Qt3DExtras::QDiffuseSpecularMaterial>(uri, 2, 10, "DiffuseSpecularMaterial");
     qmlRegisterType<Qt3DExtras::QMetalRoughMaterial>(uri, 2, 9, "MetalRoughMaterial");
     qmlRegisterRevision<Qt3DExtras::QMetalRoughMaterial, 10>(uri, 2, 10);