Texture3D

class moderngl.Texture3D

A Texture is an OpenGL object that contains one or more images that all have the same image format.

A texture can be used in two ways. It can be the source of a texture access from a Shader, or it can be used as a render target.

A Texture3D object cannot be instantiated directly, it requires a context. Use Context.texture3d() to create one.

Create

Context.texture3d(size: Tuple[int, int, int], components: int, data: Optional[Any] = None, *, alignment: int = 1, dtype: str = 'f1') Texture3D

Create a Texture3D object.

Parameters:
  • size (tuple) – The width, height and depth of the texture.

  • components (int) – The number of components 1, 2, 3 or 4.

  • data (bytes) – Content of the texture.

Keyword Arguments:
  • alignment (int) – The byte alignment 1, 2, 4 or 8.

  • dtype (str) – Data type.

Returns:

Texture3D object

Methods

Texture3D.read(*, alignment: int = 1) bytes

Read the pixel data as bytes into system memory.

Keyword Arguments:

alignment (int) – The byte alignment of the pixels.

Returns:

bytes

Texture3D.read_into(buffer: Any, *, alignment: int = 1, write_offset: int = 0) None

Read the content of the texture into a bytearray or Buffer.

The advantage of reading into a Buffer is that pixel data does not need to travel all the way to system memory:

# Reading pixel data into a bytearray
data = bytearray(8)
texture = ctx.texture3d((2, 2, 2), 1)
texture.read_into(data)

# Reading pixel data into a buffer
data = ctx.buffer(reserve=8)
texture = ctx.texture3d((2, 2, 2), 1)
texture.read_into(data)
Parameters:

buffer (Union[bytearray, Buffer]) – The buffer that will receive the pixels.

Keyword Arguments:
  • alignment (int) – The byte alignment of the pixels.

  • write_offset (int) – The write offset.

Texture3D.write(data: Any, viewport: Optional[Union[Tuple[int, int, int], Tuple[int, int, int, int, int, int]]] = None, *, alignment: int = 1) None

Update the content of the texture from byte data or a moderngl Buffer.

Examples:

# Write data from a moderngl Buffer
data = ctx.buffer(reserve=8)
texture = ctx.texture3d((2, 2, 2), 1)
texture.write(data)

# Write data from bytes
data = b'\xff\xff\xff\xff\xff\xff\xff\xff'
texture = ctx.texture3d((2, 2), 1)
texture.write(data)
Parameters:
  • data (bytes) – The pixel data.

  • viewport (tuple) – The viewport.

Keyword Arguments:

alignment (int) – The byte alignment of the pixels.

Texture3D.build_mipmaps(base: int = 0, max_level: int = 1000) None

Generate mipmaps.

This also changes the texture filter to LINEAR_MIPMAP_LINEAR, LINEAR (Will be removed in 6.x)

Keyword Arguments:
  • base (int) – The base level

  • max_level (int) – The maximum levels to generate

Texture3D.bind_to_image(unit: int, read: bool = True, write: bool = True, level: int = 0, format: int = 0) None

Bind a texture to an image unit (OpenGL 4.2 required).

This is used to bind textures to image units for shaders. The idea with image load/store is that the user can bind one of the images in a Texture to a number of image binding points (which are separate from texture image units). Shaders can read information from these images and write information to them, in ways that they cannot with textures.

It’s important to specify the right access type for the image. This can be set with the read and write arguments. Allowed combinations are:

  • Read-only: read=True and write=False

  • Write-only: read=False and write=True

  • Read-write: read=True and write=True

format specifies the format that is to be used when performing formatted stores into the image from shaders. format must be compatible with the texture’s internal format. By default the format of the texture is passed in. The format parameter is only needed when overriding this behavior.

Note that we bind the 3D textured layered making the entire texture readable and writable. It is possible to bind a specific 2D section in the future.

More information:

Parameters:
  • unit (int) – Specifies the index of the image unit to which to bind the texture

  • texture (moderngl.Texture) – The texture to bind

Keyword Arguments:
  • read (bool) – Allows the shader to read the image (default: True)

  • write (bool) – Allows the shader to write to the image (default: True)

  • level (int) – Level of the texture to bind (default: 0).

  • format (int) – (optional) The OpenGL enum value representing the format (defaults to the texture’s format)

Texture3D.use(location: int = 0) None

Bind the texture to a texture unit.

The location is the texture unit we want to bind the texture. This should correspond with the value of the sampler3D uniform in the shader because samplers read from the texture unit we assign to them:

# Define what texture unit our two sampler3D uniforms should represent
program['texture_a'] = 0
program['texture_b'] = 1
# Bind textures to the texture units
first_texture.use(location=0)
second_texture.use(location=1)
Parameters:

location (int) – The texture location/unit.

Texture3D.release() None

Release the ModernGL object.

Attributes

Texture3D.repeat_x

The x repeat flag for the texture (Default True).

Example:

# Enable texture repeat (GL_REPEAT)
texture.repeat_x = True

# Disable texture repeat (GL_CLAMP_TO_EDGE)
texture.repeat_x = False
Type:

bool

Texture3D.repeat_y

The y repeat flag for the texture (Default True).

Example:

# Enable texture repeat (GL_REPEAT)
texture.repeat_y = True

# Disable texture repeat (GL_CLAMP_TO_EDGE)
texture.repeat_y = False
Type:

bool

Texture3D.repeat_z

The z repeat flag for the texture (Default True).

Example:

# Enable texture repeat (GL_REPEAT)
texture.repeat_z = True

# Disable texture repeat (GL_CLAMP_TO_EDGE)
texture.repeat_z = False
Type:

bool

Texture3D.filter

The filter of the texture.

Type:

tuple

Texture3D.swizzle

The swizzle mask of the texture (Default 'RGBA').

The swizzle mask change/reorder the vec4 value returned by the texture() function in a GLSL shaders. This is represented by a 4 character string were each character can be:

'R' GL_RED
'G' GL_GREEN
'B' GL_BLUE
'A' GL_ALPHA
'0' GL_ZERO
'1' GL_ONE

Example:

# Alpha channel will always return 1.0
texture.swizzle = 'RGB1'

# Only return the red component. The rest is masked to 0.0
texture.swizzle = 'R000'

# Reverse the components
texture.swizzle = 'ABGR'
Type:

str

Texture3D.width

The width of the texture.

Type:

int

Texture3D.height

The height of the texture.

Type:

int

Texture3D.depth

The depth of the texture.

Type:

int

Texture3D.size

The size of the texture.

Type:

tuple

Texture3D.dtype

Data type.

Type:

str

Texture3D.components

The number of components of the texture.

Type:

int

Texture3D.glo

The internal OpenGL object.

This values is provided for debug purposes only.

Type:

int

Texture3D.mglo

Internal representation for debug purposes only.

Texture3D.extra

Any - Attribute for storing user defined objects

Texture3D.ctx

The context this object belongs to