Framebuffer#
- class moderngl.Framebuffer#
A
Framebuffer
is a collection of buffers that can be used as the destination for rendering.The buffers for Framebuffer objects reference images from either Textures or Renderbuffers. Create a
Framebuffer
usingContext.framebuffer()
.
Create#
- Context.simple_framebuffer(size: Tuple[int, int], components: int = 4, *, samples: int = 0, dtype: str = 'f1') moderngl.Framebuffer
Creates a
Framebuffer
with a single color attachment and depth buffer usingmoderngl.Renderbuffer
attachments.- Parameters
size (tuple) – The width and height of the renderbuffer.
components (int) – The number of components 1, 2, 3 or 4.
- Keyword Arguments
samples (int) – The number of samples. Value 0 means no multisample format.
dtype (str) – Data type.
- Returns
Framebuffer
object
- Context.framebuffer(color_attachments: Any = (), depth_attachment: Optional[Union[moderngl.Texture, moderngl.Renderbuffer]] = None) moderngl.Framebuffer
A
Framebuffer
is a collection of buffers that can be used as the destination for rendering. The buffers for Framebuffer objects reference images from either Textures or Renderbuffers.- Parameters
color_attachments (list) – A list of
Texture
orRenderbuffer
objects.depth_attachment (Renderbuffer or Texture) – The depth attachment.
- Returns
Framebuffer
object
Methods#
- Framebuffer.clear(red: float = 0.0, green: float = 0.0, blue: float = 0.0, alpha: float = 0.0, depth: float = 1.0, *, viewport: Optional[Union[Tuple[int, int], Tuple[int, int, int, int]]] = None, color: Optional[Tuple[float, float, float, float]] = None) None #
Clear the framebuffer.
If a viewport passed in, a scissor test will be used to clear the given viewport. This viewport take presence over the framebuffers
scissor
. Clearing can still be done with scissor if no viewport is passed in.This method also respects the
color_mask
anddepth_mask
. It can for example be used to only clear the depth or color buffer or specific components in the color buffer.If the viewport is a 2-tuple it will clear the
(0, 0, width, height)
where(width, height)
is the 2-tuple.If the viewport is a 4-tuple it will clear the given viewport.
- Parameters
red (float) – color component.
green (float) – color component.
blue (float) – color component.
alpha (float) – alpha component.
depth (float) – depth value.
- Keyword Arguments
viewport (tuple) – The viewport.
color (tuple) – Optional tuple replacing the red, green, blue and alpha arguments
- Framebuffer.read(viewport: Optional[Union[Tuple[int, int], Tuple[int, int, int, int]]] = None, components: int = 3, *, attachment: int = 0, alignment: int = 1, dtype: str = 'f1', clamp: bool = False) bytes #
Read the content of the framebuffer.
# Read the first color attachment's RGBA data data = fbo.read(components=4) # Read the second color attachment's RGB data data = fbo.read(attachment=1) # Read the depth attachment data = fbo.read(attachment=-1) # Read the lower left 10 x 10 pixels from the first color attachment data = fbo.read(viewport=(0, 0, 10, 10))
- Parameters
viewport (tuple) – The viewport.
components (int) – The number of components to read.
- Keyword Arguments
attachment (int) – The color attachment number. -1 for the depth attachment
alignment (int) – The byte alignment of the pixels.
dtype (str) – Data type.
clamp (bool) – Clamps floating point values to
[0.0, 1.0]
- Returns
bytes
- Framebuffer.read_into(buffer: Any, viewport: Optional[Union[Tuple[int, int], Tuple[int, int, int, int]]] = None, components: int = 3, *, attachment: int = 0, alignment: int = 1, dtype: str = 'f1', write_offset: int = 0) None #
Read the content of the framebuffer into a buffer.
- Parameters
buffer (bytearray) – The buffer that will receive the pixels.
viewport (tuple) – The viewport.
components (int) – The number of components to read.
- Keyword Arguments
attachment (int) – The color attachment.
alignment (int) – The byte alignment of the pixels.
dtype (str) – Data type.
write_offset (int) – The write offset.
- Framebuffer.use() None #
Bind the framebuffer. Sets the target for rendering commands.
- Framebuffer.release() None #
Release the ModernGL object.
Attributes#
- Framebuffer.viewport: Tuple[int, int, int, int]#
Get or set the viewport of the framebuffer.
- Type
tuple
- Framebuffer.scissor: Tuple[int, int, int, int]#
Get or set the scissor box of the framebuffer.
When scissor testing is enabled fragments outside the defined scissor box will be discarded. This applies to rendered geometry or
Framebuffer.clear()
.Setting is value enables scissor testing in the framebuffer. Setting the scissor to
None
disables scissor testing and reverts the scissor box to match the framebuffer size.Example:
# Enable scissor testing >>> ctx.scissor = 100, 100, 200, 100 # Disable scissor testing >>> ctx.scissor = None
- Type
tuple
- Framebuffer.color_mask: Tuple[bool, bool, bool, bool]#
The color mask of the framebuffer.
Color masking controls what components in color attachments will be affected by fragment write operations. This includes rendering geometry and clearing the framebuffer.
Default value:
(True, True, True, True)
.Examples:
# Block writing to all color components (rgba) in color attachments fbo.color_mask = False, False, False, False # Re-enable writing to color attachments fbo.color_mask = True, True, True, True # Block fragment writes to alpha channel fbo.color_mask = True, True, True, False
- Type
tuple
- Framebuffer.depth_mask: bool#
The depth mask of the framebuffer.
Depth mask enables or disables write operations to the depth buffer. This also applies when clearing the framebuffer. If depth testing is enabled fragments will still be culled, but the depth buffer will not be updated with new values. This is a very useful tool in many rendering techniques.
Default value:
True
- Type
bool
- Framebuffer.width: int#
The width of the framebuffer.
Framebuffers created by a window will only report its initial size. It’s better get size information from the window itself.
- Type
int
- Framebuffer.height: int#
The height of the framebuffer.
Framebuffers created by a window will only report its initial size. It’s better get size information from the window itself.
- Type
int
- Framebuffer.size: Tuple[int, int]#
The size of the framebuffer.
Framebuffers created by a window will only report its initial size. It’s better get size information from the window itself.
- Type
Tuple[int, int]
- Framebuffer.samples: int#
The samples of the framebuffer.
- Type
int
- Framebuffer.bits: Dict[str, str]#
The bits of the framebuffer.
- Type
dict
- Framebuffer.color_attachments: Tuple[Union[moderngl.Texture, moderngl.Renderbuffer], ...]#
The color attachments of the framebuffer.
- Type
tuple
- Framebuffer.depth_attachment: Union[moderngl.Texture, moderngl.Renderbuffer]#
The depth attachment of the framebuffer.
- Type
- Framebuffer.glo: int#
The internal OpenGL object.
This values is provided for debug purposes only.
- Type
int
- Framebuffer.mglo: Any#
Internal representation for debug purposes only.
- Framebuffer.extra: Any#
Any - Attribute for storing user defined objects
- Framebuffer.ctx: moderngl.Context#
The context this object belongs to