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SpriteLayer QML Type

A sprite layer which can contain multiple image and item layers. More...

Import Statement: import QtQuickUltralite.Layers
Since: Qt Quick Ultralite 1.7
Inherits:

Item

Properties

Detailed Description

A sprite layer can contain multiple image and item layers, which are then called sprites or sub-layers.

Most hardware platforms limit the no. of root layers that an application can have. You can overcome this by using sprite layers that contain a number of smaller layers to save memory. Although the sprite layers are useful, they do come with the following limitations:

  • There's a limited number of sub-layers per sprite layer, typically eight or less
  • Opacity will be ignored for the sub-layers.
  • Overlapping sub-layers are not blended together, showing only the pixel from the top-most sub-layer.
  • On the Renesas RH850 platform:
    • Color depth of the sprite must be compatible with the hardware layer.
    • The X position of a sprite is rounded to a multiple of two pixels for layers with 32 bit color depth, and four pixels for layers with 16 bit color depth.

SpriteLayer items have to be contained inside a Screen item.

Example usage:

Application {
    Screen {
        SpriteLayer {
            x: 10
            y: 60

            width: 100
            height: 100

            ImageLayer {
                y: 20
                source: "qrc:/images/splash.png"
            }

            ItemLayer {
                y: 40

                width: 100
                height: 60

                Text {
                    text: "Hello World"
                    anchors.centerIn: parent
                }
            }
        }
    }
}

Note: This feature may not be supported by hardware on all reference boards. For more information, see Supported Features table.

Note: This type is specific to Qt Quick Ultralite. See also the compatibility page.

See also Application, Screen, ImageLayer, ItemLayer, and Improving performance using hardware layers.

Property Documentation

depth : enumeration

The preferred color depth to use for the layer.

Possible values:

ConstantDescription
SpriteLayer.Bpp88 bits per pixel color depth, without alpha channel
SpriteLayer.Bpp1616 bits per pixel color depth, without alpha channel
SpriteLayer.Bpp16Alpha16 bits per pixel color depth, with alpha channel
SpriteLayer.Bpp2424 bits per pixel color depth, without alpha channel
SpriteLayer.Bpp3232 bits per pixel color depth, without alpha channel
SpriteLayer.Bpp32Alpha32 bits per pixel color depth, with alpha channel (default)

platformId : int

A unique value to identify the layer to the platform.

For use with platform specific API to set custom layer properties.


Available under certain Qt licenses.
Find out more.