Gl.TexImage2D (gb.opengl)
Static Sub TexImage2D ( Image As Image [ , Level As Integer, Border As Integer ] )
Specify a two-dimensional texture image.
Parameters
- 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 the following symbolic constants:
Gl.COMPRESSED_RED,
Gl.COMPRESSED_RG,
Gl.COMPRESSED_RGB,
Gl.COMPRESSED_RGBA,
Gl.COMPRESSED_SRGB,
Gl.COMPRESSED_SRGB_ALPHA,
Gl.DEPTH_COMPONENT,
Gl.DEPTH_COMPONENT16,
Gl.DEPTH_COMPONENT24,
Gl.DEPTH_COMPONENT32,
Gl.R3_G3_B2,
Gl.RED,
Gl.RG,
Gl.RGB,
Gl.RGB4,
Gl.RGB5,
Gl.RGB8,
Gl.RGB10,
Gl.RGB12,
Gl.RGB16,
Gl.RGBA,
Gl.RGBA2,
Gl.RGBA4,
Gl.RGB5_A1,
Gl.RGBA8,
Gl.RGB10_A2,
Gl.RGBA12,
Gl.RGBA16,
Gl.SRGB,
Gl.SRGB8,
Gl.SRGB_ALPHA, or
Gl.SRGB8_ALPHA8.
- 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.
The following symbolic values are accepted:
Gl.RED,
Gl.RG,
Gl.RGB,
Gl.BGR,
Gl.RGBA, and
Gl.BGRA.
- 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.
Description
Texturing allows elements of an image array to be read by shaders.
To define texture images, call
Gl.TexImage2D.
The arguments describe the parameters of the texture image,
such as height, width, width of the border, level-of-detail number
(see Gl.TexParameter),
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
Gl.GetError). 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 Gl.PixelStore).
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 Gl.BindBuffer) 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 then multiplied by the signed scale factor Gl.c_SCALE,
added to the signed bias Gl.c_BIAS,
and clamped to the range /wiki/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 then multiplied by the signed scale factor Gl.c_SCALE,
added to the signed bias Gl.c_BIAS,
and clamped to the range /wiki/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 then multiplied by the signed scale factor Gl.c_SCALE,
added to the signed bias Gl.c_BIAS,
and clamped to the range /wiki/0,1.
- Gl.RGBA
- Gl.BGRA
-
Each element contains all four components.
Each component is multiplied by the signed scale factor Gl.c_SCALE,
added to the signed bias Gl.c_BIAS,
and clamped to the range /wiki/0,1.
- Gl.DEPTH_COMPONENT
-
Each element is a single depth value.
The GL converts it to floating point, multiplies by the signed scale factor
Gl.DEPTH_SCALE, adds the signed bias Gl.DEPTH_BIAS,
and clamps to the range /wiki/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.)
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
to a linear component
is:
Assume
is the sRGB component in the range
/wiki/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 Gl.GetTexLevelParameter.
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 Gl.TexParameter for details on texture comparison.
Notes
The Gl.PixelStore 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.
Gl.TexImage2D specifies the two-dimensional texture for the current texture unit,
specified with
Gl.ActiveTexture.
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
,
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 non-power-of-two textures are not supported and the
width or
height cannot be represented as
for some
integer value of
k.
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
Gl.GetTexImage
Gl.Get with argument Gl.PIXEL_UNPACK_BUFFER_BINDING
See also
Gl.CopyTexSubImage1D,
Gl.CopyTexSubImage2D,
Gl.CopyTexSubImage3D,
Gl.PixelStore,
Gl.TexImage3D,
Gl.TexSubImage1D,
Gl.TexSubImage2D,
Gl.TexSubImage3D,
Gl.TexParameter
See original documentation on OpenGL website