public class APPLECopyTextureLevels extends java.lang.ObjectNative bindings to the APPLE_copy_texture_levels extension.
This extension provides an efficient path for copying a contiguous subset of mipmap levels from one texture to the matching subset of mipmap levels of another texture, where matches are determined by the equality of a level's dimensions.
This extension is dependent on the existence of the extension EXT_texture_storage. Immutable textures are used to guarantee that storage is allocated up front for the source and destination textures and that the internal formats of those textures are sized the same.
An efficient copy can be achieved by implementations because the internal storage requirements are the same between textures and will remain unchanged when moving data. It is expected that in all cases, moving levels from one texture to another is a simple copy operation without any necessary conversion. This extension can be used as an alternative to TEXTURE_BASE_LEVEL. In some implementations, changing the value of TEXTURE_BASE_LEVEL can incur a costly re-allocation at runtime.
Texture streaming is an expected use case for this extension. For example, a developer may want to stream in a larger base level for a given texture from a storage device. To achieve this, a copy of the current mipmap levels are made into a destination whose storage was specified to accommodate the source levels and the larger base level. The efficiency of the copy without conversion allows for the smaller mipmap levels to be in place while the larger base level is being read from the storage device and uploaded.
All Methods Static Methods Concrete Methods Modifier and Type Method Description
glCopyTextureLevelsAPPLE(int destinationTexture, int sourceTexture, int sourceBaseLevel, int sourceLevelCount)