Sub Textures

Sub Textures — Functions for creating and manipulating sub-textures.

Types and Values

Description

These functions allow high-level textures to be created that represent a sub-region of another texture. For example these can be used to implement custom texture atlasing schemes.

Functions

Types and Values

CoglSubTexture

typedef struct _CoglSubTexture CoglSubTexture;

cogl_sub_texture_new

#define cogl_sub_texture_new cogl_sub_texture_new_EXP

Creates a high-level CoglSubTexture representing a sub-region of any other CoglTexture. The sub-region must strictly lye within the bounds of the parent_texture . The returned texture implements the CoglMetaTexture interface because it's not a low level texture that hardware can understand natively.

Remember: Unless you are using high level drawing APIs such as cogl_rectangle() or other APIs documented to understand the CoglMetaTexture interface then you need to use the CoglMetaTexture interface to resolve a CoglSubTexture into a low-level texture before drawing.

Parameters

context

A CoglContext pointer

 

parent_texture

The full texture containing a sub-region you want to make a CoglSubTexture from.

 

sub_x

The top-left x coordinate of the parent region to make a texture from.

 

sub_y

The top-left y coordinate of the parent region to make a texture from.

 

sub_width

The width of the parent region to make a texture from.

 

sub_height

The height of the parent region to make a texture from.

 

Returns

A newly allocated CoglSubTexture representing a sub-region of parent_texture .

Since 1.10

Stability Level: Unstable


cogl_is_sub_texture

#define cogl_is_sub_texture cogl_is_sub_texture_EXP

Checks whether object is a CoglSubTexture.

Parameters

object

a CoglObject

 

Returns

TRUE if the passed object represents a CoglSubTexture and FALSE otherwise.

Since 1.10

Stability Level: Unstable