GLAPI/glTexImage2D

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glTexImage2D
Core in version 4.5
Core since version 1.0

glTexImage2D: specify a two-dimensional texture image

Function Definition

 void glTexImage2D(GLenum target​, GLint level​, GLint internalFormat​, GLsizei width​, GLsizei height​, GLint border​, GLenum format​, GLenum type​, const GLvoid * data​);
target
Specifies the target texture. Must be GL_TEXTURE_2D, GL_PROXY_TEXTURE_2D, GL_TEXTURE_1D_ARRAY, GL_PROXY_TEXTURE_1D_ARRAY, GL_TEXTURE_RECTANGLE, GL_PROXY_TEXTURE_RECTANGLE, GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, GL_TEXTURE_CUBE_MAP_POSITIVE_Y, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, GL_TEXTURE_CUBE_MAP_POSITIVE_Z, GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or GL_PROXY_TEXTURE_CUBE_MAP.
level
Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image. If target​ is GL_TEXTURE_RECTANGLE or GL_PROXY_TEXTURE_RECTANGLE, level​ must be 0.
internalFormat
Specifies the number of color components in the texture. Must be one of base internal formats given in Table 1, one of the sized internal formats given in Table 2, or one of the compressed internal formats given in Table 3, below.
width
Specifies the width of the texture image. All implementations support texture images that are at least 1024 texels wide.
height
Specifies the height of the texture image, or the number of layers in a texture array, in the case of the GL_TEXTURE_1D_ARRAY and GL_PROXY_TEXTURE_1D_ARRAY targets. All implementations support 2D texture images that are at least 1024 texels high, and texture arrays that are at least 256 layers deep.
border
This value must be 0.
format
Specifies the format of the pixel data. For transfers of depth, stencil, or depth/stencil data, you must use GL_DEPTH_COMPONENT, GL_STENCIL_INDEX, or GL_DEPTH_STENCIL, where appropriate. For transfers of normalized integer or floating-point color image data, you must use one of the following: GL_RED, GL_GREEN, GL_BLUE, GL_RG, GL_RGB, GL_BGR, GL_RGBA, and GL_BGRA. For transfers of non-normalized integer data, you must use one of the following: GL_RED_INTEGER, GL_GREEN_INTEGER, GL_BLUE_INTEGER, GL_RG_INTEGER, GL_RGB_INTEGER, GL_BGR_INTEGER, GL_RGBA_INTEGER, and GL_BGRA_INTEGER.
type
Specifies the data type of the pixel data. The following symbolic values are accepted: GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, GL_FLOAT, GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, and GL_UNSIGNED_INT_2_10_10_10_REV.
data
Specifies a pointer to the image data in memory, or if a buffer is bound to GL_PIXEL_UNPACK_BUFFER, this provides an integer offset into the bound buffer object. If a buffer is not bound to GL_PIXEL_UNPACK_BUFFER, and this parameter is NULL, no Pixel Transfer will be performed.


Description

Texturing allows elements of an image array to be read by shaders.

To define texture images, call glTexImage2D. The arguments describe the parameters of the texture image, such as height, width, width of the border, level-of-detail number (see glTexParameter), and number of color components provided. The last three arguments describe how the image is represented in memory.

If target​ is GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_ARRAY, GL_PROXY_TEXTURE_CUBE_MAP, or GL_PROXY_TEXTURE_RECTANGLE, no data is read from data​, but all of the texture image state is recalculated, checked for consistency, and checked against the implementation's capabilities. If the implementation cannot handle a texture of the requested texture size, it sets all of the image state to 0, but does not generate an error (see glGetError). To query for an entire mipmap array, use an image array level greater than or equal to 1.

If target​ is GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE or one of the GL_TEXTURE_CUBE_MAP targets, data is read from data​ as a sequence of signed or unsigned bytes, shorts, or longs, or single-precision floating-point values, depending on type​. These values are grouped into sets of one, two, three, or four values, depending on format​, to form elements. Each data byte is treated as eight 1-bit elements, with bit ordering determined by GL_UNPACK_LSB_FIRST (see glPixelStore).

If target​ is GL_TEXTURE_1D_ARRAY, data is interpreted as an array of one-dimensional images.

If a non-zero named buffer object is bound to the GL_PIXEL_UNPACK_BUFFER target (see glBindBuffer) while a texture image is specified, data​ is treated as a byte offset into the buffer object's data store.

The first element corresponds to the lower left corner of the texture image. Subsequent elements progress left-to-right through the remaining texels in the lowest row of the texture image, and then in successively higher rows of the texture image. The final element corresponds to the upper right corner of the texture image.

format​ determines the composition of each element in data​. It can assume one of these symbolic values:

GL_RED
Each element is a single red component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0 for green and blue, and 1 for alpha. Each component is clamped to the range [0,1].
GL_RG
Each element is a red/green double. The GL converts it to floating point and assembles it into an RGBA element by attaching 0 for blue, and 1 for alpha. Each component is clamped to the range [0,1].
GL_RGB
 ; GL_BGR
Each element is an RGB triple. The GL converts it to floating point and assembles it into an RGBA element by attaching 1 for alpha. Each component is clamped to the range [0,1].
GL_RGBA
 ; GL_BGRA
Each element contains all four components. Each component is clamped to the range [0,1].
GL_DEPTH_COMPONENT
Each element is a single depth value. The GL converts it to floating point and clamps to the range [0,1].
GL_DEPTH_STENCIL
Each element is a pair of depth and stencil values. The depth component of the pair is interpreted as in GL_DEPTH_COMPONENT. The stencil component is interpreted based on specified the depth + stencil internal format.

If an application wants to store the texture at a certain resolution or in a certain format, it can request the resolution and format with internalFormat​. The GL will choose an internal representation that closely approximates that requested by internalFormat​, but it may not match exactly. (The representations specified by GL_RED, GL_RG, GL_RGB, and GL_RGBA must match exactly.)

internalFormat​ may be one of the formats from the tables below:

Base Internal Formats
Base Internal Format RGBA, Depth and Stencil Values Internal Components
GL_DEPTH_COMPONENT Depth D
GL_DEPTH_STENCIL Depth, Stencil D, S
GL_STENCIL_INDEX Stencil S
GL_RED Red R
GL_RG Red, Green R, G
GL_RGB Red, Green, Blue R, G, B
GL_RGBA Red, Green, Blue, Alpha R, G, B, A


Sized Internal Formats
Component Bitdepth
Sized Internal Format Base Internal Format Red Green Blue Alpha Shared
GL_R8 GL_RED 8
GL_R8_SNORM GL_RED s8
GL_R16 GL_RED 16
GL_R16_SNORM GL_RED s16
GL_RG8 GL_RG 8 8
GL_RG8_SNORM GL_RG s8 s8
GL_RG16 GL_RG 16 16
GL_RG16_SNORM GL_RG s16 s16
GL_R3_G3_B2 GL_RGB 3 3 2
GL_RGB4 GL_RGB 4 4 4
GL_RGB5 GL_RGB 5 5 5
GL_RGB8 GL_RGB 8 8 8
GL_RGB8_SNORM GL_RGB s8 s8 s8
GL_RGB10 GL_RGB 10 10 10
GL_RGB12 GL_RGB 12 12 12
GL_RGB16_SNORM GL_RGB 16 16 16
GL_RGBA2 GL_RGB 2 2 2 2
GL_RGBA4 GL_RGB 4 4 4 4
GL_RGB5_A1 GL_RGBA 5 5 5 1
GL_RGBA8 GL_RGBA 8 8 8 8
GL_RGBA8_SNORM GL_RGBA s8 s8 s8 s8
GL_RGB10_A2 GL_RGBA 10 10 10 2
GL_RGB10_A2UI GL_RGBA ui10 ui10 ui10 ui2
GL_RGBA12 GL_RGBA 12 12 12 12
GL_RGBA16 GL_RGBA 16 16 16 16
GL_SRGB8 GL_RGB 8 8 8
GL_SRGB8_ALPHA8 GL_RGBA 8 8 8 8
GL_R16F GL_RED f16
GL_RG16F GL_RG f16 f16
GL_RGB16F GL_RGB f16 f16 f16
GL_RGBA16F GL_RGBA f16 f16 f16 f16
GL_R32F GL_RED f32
GL_RG32F GL_RG f32 f32
GL_RGB32F GL_RGB f32 f32 f32
GL_RGBA32F GL_RGBA f32 f32 f32 f32
GL_R11F_G11F_B10F GL_RGB f11 f11 f10
GL_RGB9_E5 GL_RGB 9 9 9 5
GL_R8I GL_RED i8
GL_R8UI GL_RED ui8
GL_R16I GL_RED i16
GL_R16UI GL_RED ui16
GL_R32I GL_RED i32
GL_R32UI GL_RED ui32
GL_RG8I GL_RG i8 i8
GL_RG8UI GL_RG ui8 ui8
GL_RG16I GL_RG i16 i16
GL_RG16UI GL_RG ui16 ui16
GL_RG32I GL_RG i32 i32
GL_RG32UI GL_RG ui32 ui32
GL_RGB8I GL_RGB i8 i8 i8
GL_RGB8UI GL_RGB ui8 ui8 ui8
GL_RGB16I GL_RGB i16 i16 i16
GL_RGB16UI GL_RGB ui16 ui16 ui16
GL_RGB32I GL_RGB i32 i32 i32
GL_RGB32UI GL_RGB ui32 ui32 ui32
GL_RGBA8I GL_RGBA i8 i8 i8 i8
GL_RGBA8UI GL_RGBA ui8 ui8 ui8 ui8
GL_RGBA16I GL_RGBA i16 i16 i16 i16
GL_RGBA16UI GL_RGBA ui16 ui16 ui16 ui16
GL_RGBA32I GL_RGBA i32 i32 i32 i32
GL_RGBA32UI GL_RGBA ui32 ui32 ui32 ui32


Sized Depth and Stencil Internal Formats
Component Bitdepth
Sized Internal Format Base Internal Format Depth Stencil
GL_DEPTH_COMPONENT16 GL_DEPTH_COMPONENT 16
GL_DEPTH_COMPONENT24 GL_DEPTH_COMPONENT 24
GL_DEPTH_COMPONENT32 GL_DEPTH_COMPONENT 32
GL_DEPTH_COMPONENT32F GL_DEPTH_COMPONENT f32
GL_DEPTH24_STENCIL8 GL_DEPTH_STENCIL 24 8
GL_DEPTH32F_STENCIL8 GL_DEPTH_STENCIL f32 8
GL_STENCIL_INDEX8 GL_STENCIL_INDEX 8


Compressed Internal Formats
Compressed Internal Format Base Internal Format Type
GL_COMPRESSED_RED GL_RED Generic
GL_COMPRESSED_RG GL_RG Generic
GL_COMPRESSED_RGB GL_RGB Generic
GL_COMPRESSED_RGBA GL_RGBA Generic
GL_COMPRESSED_SRGB GL_RGB Generic
GL_COMPRESSED_SRGB_ALPHA GL_RGBA Generic
GL_COMPRESSED_RED_RGTC1 GL_RED Specific
GL_COMPRESSED_SIGNED_RED_RGTC1 GL_RED Specific
GL_COMPRESSED_RG_RGTC2 GL_RG Specific
GL_COMPRESSED_SIGNED_RG_RGTC2 GL_RG Specific
GL_COMPRESSED_RGBA_BPTC_UNORM GL_RGBA Specific
GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM GL_RGBA Specific
GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT GL_RGB Specific
GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT GL_RGB Specific
S3TC formats
GL_COMPRESSED_RGB_S3TC_DXT1_EXT GL_RGB Specific
GL_COMPRESSED_SRGB_S3TC_DXT1_EXT GL_RGB Specific
GL_COMPRESSED_RGBA_S3TC_DXT1_EXT GL_RGBA Specific
GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT GL_RGBA Specific
GL_COMPRESSED_RGBA_S3TC_DXT3_EXT GL_RGBA Specific
GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT GL_RGBA Specific
GL_COMPRESSED_RGBA_S3TC_DXT5_EXT GL_RGBA Specific
GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT GL_RGBA Specific


If the internalFormat​ parameter is one of the generic compressed formats, GL_COMPRESSED_RED, GL_COMPRESSED_RG, GL_COMPRESSED_RGB, or GL_COMPRESSED_RGBA, the GL will replace the internal format with the symbolic constant for a specific internal format and compress the texture before storage. If no corresponding internal format is available, or the GL can not compress that image for any reason, the internal format is instead replaced with a corresponding base internal format.

If the internalFormat​ parameter is GL_SRGB, GL_SRGB8, GL_SRGB_ALPHA, or GL_SRGB8_ALPHA8, the texture is treated as if the red, green, or blue components are encoded in the sRGB color space. Any alpha component is left unchanged. The conversion from the sRGB encoded component cs to a linear component cl is:

c_{l}={\begin{cases}{\tfrac  {c_{s}}{12.92}},&{\text{if }}c_{s}\leq 0.04045\\\left({\tfrac  {c_{s}+0.055}{1.055}}\right)^{{2.4}},&{\text{if }}c_{s}>0.04045\end{cases}}


Assume cs is the sRGB component in the range [0,1].

Use the GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_ARRAY, GL_PROXY_TEXTURE_RECTANGLE, or GL_PROXY_TEXTURE_CUBE_MAP target to try out a resolution and format. The implementation will update and recompute its best match for the requested storage resolution and format. To then query this state, call glGetTexLevelParameter. If the texture cannot be accommodated, texture state is set to 0.

A one-component texture image uses only the red component of the RGBA color extracted from data​. A two-component image uses the R and G values. A three-component image uses the R, G, and B values. A four-component image uses all of the RGBA components.

Image-based shadowing can be enabled by comparing texture r coordinates to depth texture values to generate a boolean result. See glTexParameter for details on texture comparison.

Notes

The glPixelStore mode affects texture images.

data​ may be a null pointer. In this case, texture memory is allocated to accommodate a texture of width width​ and height height​. You can then download subtextures to initialize this texture memory. The image is undefined if the user tries to apply an uninitialized portion of the texture image to a primitive.

glTexImage2D specifies the two-dimensional texture for the current texture unit, specified with glActiveTexture.

GL_STENCIL_INDEX may be used for format​ only if the GL version is 4.4 or higher.

Errors

GL_INVALID_ENUM is generated if target​ is not GL_TEXTURE_2D, GL_TEXTURE_1D_ARRAY, GL_TEXTURE_RECTANGLE, GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_ARRAY, GL_PROXY_TEXTURE_RECTANGLE, GL_PROXY_TEXTURE_CUBE_MAP, GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, GL_TEXTURE_CUBE_MAP_POSITIVE_Y, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, GL_TEXTURE_CUBE_MAP_POSITIVE_Z, or GL_TEXTURE_CUBE_MAP_NEGATIVE_Z.

GL_INVALID_ENUM is generated if target​ is one of the six cube map 2D image targets and the width and height parameters are not equal.

GL_INVALID_ENUM is generated if type​ is not a type constant.

GL_INVALID_VALUE is generated if width​ is less than 0 or greater than GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if target​ is not GL_TEXTURE_1D_ARRAY or GL_PROXY_TEXTURE_1D_ARRAY and height​ is less than 0 or greater than GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if target​ is GL_TEXTURE_1D_ARRAY or GL_PROXY_TEXTURE_1D_ARRAY and height​ is less than 0 or greater than GL_MAX_ARRAY_TEXTURE_LAYERS.

GL_INVALID_VALUE is generated if level​ is less than 0.

GL_INVALID_VALUE may be generated if level​ is greater than log2(max), where max is the returned value of GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if internalFormat​ is not one of the accepted resolution and format symbolic constants.

GL_INVALID_VALUE is generated if width​ or height​ is less than 0 or greater than GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if border​ is not 0.

GL_INVALID_OPERATION is generated if type​ is one of GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, or GL_UNSIGNED_INT_10F_11F_11F_REV, and format​ is not GL_RGB.

GL_INVALID_OPERATION is generated if type​ is one of GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV, or GL_UNSIGNED_INT_5_9_9_9_REV, and format​ is neither GL_RGBA nor GL_BGRA.

GL_INVALID_OPERATION is generated if target​ is not GL_TEXTURE_2D, GL_PROXY_TEXTURE_2D, GL_TEXTURE_RECTANGLE, or GL_PROXY_TEXTURE_RECTANGLE, and internalFormat​ is GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32F.

GL_INVALID_OPERATION is generated if format​ is GL_DEPTH_COMPONENT and internalFormat​ is not GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32F.

GL_INVALID_OPERATION is generated if internalFormat​ is GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32F, and format​ is not GL_DEPTH_COMPONENT.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the buffer object's data store is currently mapped.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the data would be unpacked from the buffer object such that the memory reads required would exceed the data store size.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and data​ is not evenly divisible into the number of bytes needed to store in memory a datum indicated by type​.

GL_INVALID_VALUE is generated if target​ is GL_TEXTURE_RECTANGLE or GL_PROXY_TEXTURE_RECTANGLE and level​ is not 0.

Associated Gets

glGetTexImage

glGet with argument GL_PIXEL_UNPACK_BUFFER_BINDING

See Also

glActiveTexture, glBindTexture, glTexImage1D, glTexImage2DMultisample, glTexImage3D, glTexImage3DMultisample, glTexSubImage2D, glPixelStore

Required formats

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2011-2013 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.