WebGLRenderingContext.texSubImage2D()

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

Syntax

// WebGL 1:
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, ArrayBufferView? pixels);
void gl.texSubImage2D(target, level, xoffset, yoffset, format, type, ImageData? pixels);
void gl.texSubImage2D(target, level, xoffset, yoffset, format, type, HTMLImageElement? pixels);
void gl.texSubImage2D(target, level, xoffset, yoffset, format, type, HTMLCanvasElement? pixels);
void gl.texSubImage2D(target, level, xoffset, yoffset, format, type, HTMLVideoElement? pixels);
void gl.texSubImage2D(target, level, xoffset, yoffset, format, type, ImageBitmap? pixels);

// WebGL 2:
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, GLintptr offset);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, HTMLCanvasElement source);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, HTMLImageElement source);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, HTMLVideoElement source);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, ImageBitmap source);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, ImageData source);
void gl.texSubImage2D(target, level, xoffset, yoffset, width, height, format, type, ArrayBufferView srcData, 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.

Examples

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

Specifications

Specification
WebGL Specification (WebGL)
# TEXSUBIMAGE2D
WebGL 2.0 Specification (WebGL 2.0)
# 3.7.6

Browser compatibility

BCD tables only load in the browser

See also