Package org.lwjgl.opengl

Class EXTTextureBufferObject

java.lang.Object
org.lwjgl.opengl.EXTTextureBufferObject
public class EXTTextureBufferObject extends Object
Native bindings to the EXT_texture_buffer_object extension.

This extension provides a new texture type, called a buffer texture. Buffer textures are one-dimensional arrays of texels whose storage comes from an attached buffer object. When a buffer object is bound to a buffer texture, a format is specified, and the data in the buffer object is treated as an array of texels of the specified format.

The use of a buffer object to provide storage allows the texture data to be specified in a number of different ways: via buffer object loads (BufferData), direct CPU writes (MapBuffer), framebuffer readbacks (EXT_pixel_buffer_object extension). A buffer object can also be loaded by transform feedback (NV_transform_feedback extension), which captures selected transformed attributes of vertices processed by the GL. Several of these mechanisms do not require an extra data copy, which would be required when using conventional TexImage-like entry points.

Buffer textures do not support mipmapping, texture lookups with normalized floating-point texture coordinates, and texture filtering of any sort, and may not be used in fixed-function fragment processing. They can be accessed via single texel fetch operations in programmable shaders. For assembly shaders (NV_gpu_program4), the TXF instruction is used. For GLSL (EXT_gpu_shader4), a new sampler type and texel fetch function are used.

Buffer textures can be substantially larger than equivalent one-dimensional textures; the maximum texture size supported for buffer textures in the initial implementation of this extension is 2^27 texels, versus 2^13 (8192) texels for otherwise equivalent one-dimensional textures. (Note that this extension only guarantees support for buffer textures with 2^16 texels, but we expect most implementations to exceed that substantially.) When a buffer object is attached to a buffer texture, a size is not specified; rather, the number of texels in the texture is taken by dividing the size of the buffer object by the size of each texel.

Requires OpenGL 2.0 and EXT_gpu_shader4 or NV_gpu_program4.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    GL_MAX_TEXTURE_BUFFER_SIZE_EXT
    Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
    static final int
    GL_TEXTURE_BINDING_BUFFER_EXT
    Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
    static final int
    GL_TEXTURE_BUFFER_DATA_STORE_BINDING_EXT
    Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
    static final int
    GL_TEXTURE_BUFFER_EXT
    Accepted by the target parameter of BindBuffer, BufferData, BufferSubData, MapBuffer, BindTexture, UnmapBuffer, GetBufferSubData, GetBufferParameteriv, GetBufferPointerv, and TexBufferEXT, and the pname parameter of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
    static final int
    GL_TEXTURE_BUFFER_FORMAT_EXT
    Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.

  • Method Summary

    Modifier and Type
    Method
    Description
    static void
    glTexBufferEXT(int target, int internalformat, int buffer)
     

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • GL_TEXTURE_BUFFER_EXT

      public static final int GL_TEXTURE_BUFFER_EXT
      Accepted by the target parameter of BindBuffer, BufferData, BufferSubData, MapBuffer, BindTexture, UnmapBuffer, GetBufferSubData, GetBufferParameteriv, GetBufferPointerv, and TexBufferEXT, and the pname parameter of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
      See Also:

    • GL_MAX_TEXTURE_BUFFER_SIZE_EXT

      public static final int GL_MAX_TEXTURE_BUFFER_SIZE_EXT
      Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
      See Also:

    • GL_TEXTURE_BINDING_BUFFER_EXT

      public static final int GL_TEXTURE_BINDING_BUFFER_EXT
      Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
      See Also:

    • GL_TEXTURE_BUFFER_DATA_STORE_BINDING_EXT

      public static final int GL_TEXTURE_BUFFER_DATA_STORE_BINDING_EXT
      Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
      See Also:

    • GL_TEXTURE_BUFFER_FORMAT_EXT

      public static final int GL_TEXTURE_BUFFER_FORMAT_EXT
      Accepted by the pname parameters of GetBooleanv, GetDoublev, GetFloatv, and GetIntegerv.
      See Also:

  • Method Details

    • glTexBufferEXT

      public static void glTexBufferEXT(int target, int internalformat, int buffer)