QGoochMaterial Class

class Qt3DExtras::QGoochMaterial

The QGoochMaterial provides a material that implements the Gooch shading model, popular in CAD and CAM applications. More...

Header: #include <QGoochMaterial>
CMake: find_package(Qt6 REQUIRED COMPONENTS 3dextras)
target_link_libraries(mytarget PRIVATE Qt6::3dextras)
qmake: QT += 3dextras
Inherits: Qt3DRender::QMaterial

Properties

Public Functions

QGoochMaterial(Qt3DCore::QNode *parent = nullptr)
float alpha() const
float beta() const
QColor cool() const
QColor diffuse() const
float shininess() const
QColor specular() const
QColor warm() const

Public Slots

void setAlpha(float alpha)
void setBeta(float beta)
void setCool(const QColor &cool)
void setDiffuse(const QColor &diffuse)
void setShininess(float shininess)
void setSpecular(const QColor &specular)
void setWarm(const QColor &warm)

Signals

void alphaChanged(float alpha)
void betaChanged(float beta)
void coolChanged(const QColor &cool)
void diffuseChanged(const QColor &diffuse)
void shininessChanged(float shininess)
void specularChanged(const QColor &specular)
void warmChanged(const QColor &warm)

Detailed Description

The Gooch lighting model uses both color and brightness to help show the curvature of 3D surfaces. This is often better than models such as Phong that rely purely upon changes in brightness. In situations such as in CAD and CAM applications where photorealism is not a goal, the Gooch shading model in conjunction with some kind of silhouette edge inking is a popular solution.

The Gooch lighting model is explained fully in the original Gooch paper. The Gooch model mixes a diffuse object color with a user-provided cool color and warm color to produce the end points of a color ramp that is used to shade the object based upon the cosine of the angle between the vector from the fragment to the light source and the fragment's normal vector. Optionally, a specular highlight can be added on top. The relative contributions to the cool and warm colors by the diffuse color are controlled by the alpha and beta properties respecitvely.

This material uses an effect with a single render pass approach and performs per fragment lighting. Techniques are provided for OpenGL 2, OpenGL 3 or above as well as OpenGL ES 2.

Property Documentation

alpha : float

Holds the current alpha value. The start point of the color ramp used by the Gooch shader is calculated as {c = cool + alpha * diffuse}.

Access functions:

float alpha() const
void setAlpha(float alpha)

Notifier signal:

void alphaChanged(float alpha)

beta : float

Holds the current beta value. The start point of the color ramp used by the Gooch shader is calculated as {c = warm + beta * diffuse}.

Access functions:

float beta() const
void setBeta(float beta)

Notifier signal:

void betaChanged(float beta)

cool : QColor

Holds the current cool color.

Access functions:

QColor cool() const
void setCool(const QColor &cool)

Notifier signal:

void coolChanged(const QColor &cool)

diffuse : QColor

Holds the current diffuse color.

Access functions:

QColor diffuse() const
void setDiffuse(const QColor &diffuse)

Notifier signal:

void diffuseChanged(const QColor &diffuse)

shininess : float

Holds the current shininess value. Higher values of shininess result in a smaller and brighter highlight.

Access functions:

float shininess() const
void setShininess(float shininess)

Notifier signal:

void shininessChanged(float shininess)

specular : QColor

Holds the current specular color.

Access functions:

QColor specular() const
void setSpecular(const QColor &specular)

Notifier signal:

void specularChanged(const QColor &specular)

warm : QColor

Holds the current warm color.

Access functions:

QColor warm() const
void setWarm(const QColor &warm)

Notifier signal:

void warmChanged(const QColor &warm)

Member Function Documentation

[explicit] QGoochMaterial::QGoochMaterial(Qt3DCore::QNode *parent = nullptr)

Constructs a new QGoochMaterial instance with parent object parent.

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