Qt Quick 3D - Instanced Rendering Example▲
This example shows how do instanced rendering using the basic QML API.
The spaceship and asteroid models were created using the Blender 3D modeling tool, and imported with https://.
Random instancing▲
We use https:// to make a random table that defines our asteroid field:
RandomInstancing {
id: randomInstancing
instanceCount: 1500
position: InstanceRange {
from: Qt.vector3d(-300, -200, -500)
to: Qt.vector3d(300, 200, 200)
}
scale: InstanceRange {
from: Qt.vector3d(1, 1, 1)
to: Qt.vector3d(10, 10, 10)
proportional: true
}
rotation: InstanceRange {
from: Qt.vector3d(0, 0, 0)
to: Qt.vector3d(360, 360, 360)
}
color: InstanceRange {
from: "grey"
to: "white"
proportional: true
}
randomSeed: 2021
}Position and rotation are allowed to vary freely. Scaling is set to be uniform in all directions and colors are grayscale. This is done by setting the https:// attribute.
The spaceships are placed manually using https://:
InstanceListEntry {
id: redShip
position: Qt.vector3d(50, 10, 100)
eulerRotation: Qt.vector3d(0, 180, 0)
color: "red"
NumberAnimation on position.x {
from: 50
to: -70
duration: 8000
}
}
InstanceListEntry {
id: greenShip
position: Qt.vector3d(0, 0, -60)
eulerRotation: Qt.vector3d(-10, 0, 30)
color: "green"
}
InstanceListEntry {
id: blueShip
position: Qt.vector3d(-100, -100, 0)
color: "blue"
}
InstanceList {
id: manualInstancing
instances: [ redShip, greenShip, blueShip ]
}The properties of https:// are bindable: here we animate the red ship so it crosses the path of the camera.
Finally we apply the instancing tables to the objects:
Asteroid {
instancing: randomInstancing
NumberAnimation on eulerRotation.x {
from: 0
to: 360
duration: 11000
loops: Animation.Infinite
}
}
SimpleSpaceship {
instancing: manualInstancing
}By animating the rotation of the asteroid model, all of the instances will rotate without having to change the contents of the instance table. Since the asteroid instances have random rotations, all the asteroids will rotate around different axes.
List of Files▲
Files:
List of Files▲
-
instancing/Asteroid.qml
-
instancing/CMakeLists.txt
-
instancing/SimpleSpaceship.qml
-
instancing/instancing.pro
-
instancing/main.cpp
-
instancing/main.qml
-
instancing/qml.qrc