WebGLRenderingContext.texSubImage2D()

The WebGLRenderingContext.texSubImage2D() method of the WebGL API specifies a sub-rectangle of the current texture.

Syntax

// WebGL1
texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, pixels) // pixels is a TypedArray or a DataView
texSubImage2D(target, level, xoffset, yoffset, format, type, pixels)

// WebGL2
texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, offset)
texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, source)
texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, pixels, srcOffset)

Parameters

target

A GLenum specifying the binding point (target) of the active texture. Possible values:

  • gl.TEXTURE_2D: A two-dimensional texture.
  • gl.TEXTURE_CUBE_MAP_POSITIVE_X: Positive X face for a cube-mapped texture.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_X: Negative X face for a cube-mapped texture.
  • gl.TEXTURE_CUBE_MAP_POSITIVE_Y: Positive Y face for a cube-mapped texture.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_Y: Negative Y face for a cube-mapped texture.
  • gl.TEXTURE_CUBE_MAP_POSITIVE_Z: Positive Z face for a cube-mapped texture.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_Z: Negative Z face for a cube-mapped texture.
level

A GLint specifying the level of detail. Level 0 is the base image level and level n is the nth mipmap reduction level.

xoffset

A GLint specifying the lower left texel x coordinate of a width-wide by height-wide rectangular subregion of the texture array.

yoffset

A GLint specifying the lower left texel y coordinate of a width-wide by height-wide rectangular subregion of the texture array.

width

A GLsizei specifying the width of the texture in texels.

height

A GLsizei specifying the height of the texture in texels.

format

A GLenum specifying the format of the texel data. Possible values:

  • gl.ALPHA: Discards the red, green and blue components and reads the alpha component.
  • gl.RGB: Discards the alpha components and reads the red, green and blue components.
  • gl.RGBA: Red, green, blue and alpha components are read from the color buffer.
  • gl.LUMINANCE: Each color component is a luminance component, alpha is 1.0.
  • gl.LUMINANCE_ALPHA: Each component is a luminance/alpha component.

When using the EXT_sRGB extension:

  • ext.SRGB_EXT
  • ext.SRGB_ALPHA_EXT

When using a WebGL 2 context, the following values are available additionally:

  • gl.RED
  • gl.RG
  • gl.RED_INTEGER
  • gl.RG_INTEGER
  • gl.RGB_INTEGER
  • gl.RGBA_INTEGER
type

A GLenum specifying the data type of the texel data. Possible values:

  • gl.UNSIGNED_BYTE: 8 bits per channel for gl.RGBA
  • gl.UNSIGNED_SHORT_5_6_5: 5 red bits, 6 green bits, 5 blue bits.
  • gl.UNSIGNED_SHORT_4_4_4_4: 4 red bits, 4 green bits, 4 blue bits, 4 alpha bits.
  • gl.UNSIGNED_SHORT_5_5_5_1: 5 red bits, 5 green bits, 5 blue bits, 1 alpha bit.

When using the OES_texture_float extension:

  • gl.FLOAT

When using the OES_texture_half_float extension:

  • gl.HALF_FLOAT_OES

When using a WebGL 2 context, the following values are available additionally:

  • gl.BYTE
  • gl.UNSIGNED_SHORT
  • gl.SHORT
  • gl.UNSIGNED_INT
  • gl.INT
  • gl.HALF_FLOAT
  • gl.FLOAT
  • gl.UNSIGNED_INT_2_10_10_10_REV
  • gl.UNSIGNED_INT_10F_11F_11F_REV
  • gl.UNSIGNED_INT_5_9_9_9_REV
  • gl.UNSIGNED_INT_24_8
  • gl.FLOAT_32_UNSIGNED_INT_24_8_REV (pixels must be null)
pixels

One of the following objects can be used as a pixel source for the texture:

offset

(WebGL 2 only) A GLintptr byte offset into the WebGLBuffer's data store. Used to upload data to the currently bound WebGLTexture from the WebGLBuffer bound to the PIXEL_UNPACK_BUFFER target.

Return value

None (undefined).

Examples

gl.texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, gl.RGBA, gl.UNSIGNED_BYTE, image);

Specifications

Specification
WebGL Specification
# TEXSUBIMAGE2D
WebGL 2.0 Specification
# 3.7.6

Browser compatibility

BCD tables only load in the browser

See also