Trait FramebufferExt

pub trait FramebufferExt: 'static {
    // Required methods
    fn add_fence_callback<P: Fn(&Fence) + 'static>(
        &self,
        callback: P,
    ) -> Option<FenceClosure>;
    fn allocate(&self) -> Result<bool, Error>;
    fn cancel_fence_callback(&self, closure: &mut FenceClosure);
    fn clear(&self, buffers: c_ulong, color: &Color);
    fn clear4f(
        &self,
        buffers: c_ulong,
        red: f32,
        green: f32,
        blue: f32,
        alpha: f32,
    );
    fn discard_buffers(&self, buffers: c_ulong);
    fn draw_multitextured_rectangle(
        &self,
        pipeline: &Pipeline,
        x_1: f32,
        y_1: f32,
        x_2: f32,
        y_2: f32,
        tex_coords: &[f32],
    );
    fn draw_rectangle(
        &self,
        pipeline: &Pipeline,
        x_1: f32,
        y_1: f32,
        x_2: f32,
        y_2: f32,
    );
    fn draw_textured_rectangle(
        &self,
        pipeline: &Pipeline,
        x_1: f32,
        y_1: f32,
        x_2: f32,
        y_2: f32,
        s_1: f32,
        t_1: f32,
        s_2: f32,
        t_2: f32,
    );
    fn finish(&self);
    fn frustum(
        &self,
        left: f32,
        right: f32,
        bottom: f32,
        top: f32,
        z_near: f32,
        z_far: f32,
    );
    fn get_alpha_bits(&self) -> i32;
    fn get_blue_bits(&self) -> i32;
    fn get_color_mask(&self) -> ColorMask;
    fn get_context(&self) -> Option<Context>;
    fn get_depth_bits(&self) -> i32;
    fn get_depth_texture(&self) -> Option<Texture>;
    fn get_depth_texture_enabled(&self) -> bool;
    fn get_depth_write_enabled(&self) -> bool;
    fn get_dither_enabled(&self) -> bool;
    fn get_green_bits(&self) -> i32;
    fn get_height(&self) -> i32;
    fn get_is_stereo(&self) -> bool;
    fn get_modelview_matrix(&self) -> Matrix;
    fn get_projection_matrix(&self) -> Matrix;
    fn get_red_bits(&self) -> i32;
    fn get_samples_per_pixel(&self) -> i32;
    fn get_stereo_mode(&self) -> StereoMode;
    fn get_viewport_height(&self) -> f32;
    fn get_viewport_width(&self) -> f32;
    fn get_viewport_x(&self) -> f32;
    fn get_viewport_y(&self) -> f32;
    fn get_width(&self) -> i32;
    fn identity_matrix(&self);
    fn orthographic(
        &self,
        x_1: f32,
        y_1: f32,
        x_2: f32,
        y_2: f32,
        near: f32,
        far: f32,
    );
    fn perspective(&self, fov_y: f32, aspect: f32, z_near: f32, z_far: f32);
    fn pop_clip(&self);
    fn pop_matrix(&self);
    fn push_matrix(&self);
    fn push_primitive_clip(
        &self,
        primitive: &Primitive,
        bounds_x1: f32,
        bounds_y1: f32,
        bounds_x2: f32,
        bounds_y2: f32,
    );
    fn push_rectangle_clip(&self, x_1: f32, y_1: f32, x_2: f32, y_2: f32);
    fn push_scissor_clip(&self, x: i32, y: i32, width: i32, height: i32);
    fn read_pixels(
        &self,
        x: i32,
        y: i32,
        width: i32,
        height: i32,
        format: PixelFormat,
        pixels: &[u8],
    ) -> bool;
    fn read_pixels_into_bitmap(
        &self,
        x: i32,
        y: i32,
        source: ReadPixelsFlags,
        bitmap: &Bitmap,
    ) -> bool;
    fn resolve_samples(&self);
    fn resolve_samples_region(&self, x: i32, y: i32, width: i32, height: i32);
    fn rotate(&self, angle: f32, x: f32, y: f32, z: f32);
    fn rotate_euler(&self, euler: &Euler);
    fn rotate_quaternion(&self, quaternion: &Quaternion);
    fn scale(&self, x: f32, y: f32, z: f32);
    fn set_color_mask(&self, color_mask: ColorMask);
    fn set_depth_texture_enabled(&self, enabled: bool);
    fn set_depth_write_enabled(&self, depth_write_enabled: bool);
    fn set_dither_enabled(&self, dither_enabled: bool);
    fn set_modelview_matrix(&self, matrix: &Matrix);
    fn set_projection_matrix(&self, matrix: &Matrix);
    fn set_samples_per_pixel(&self, samples_per_pixel: i32);
    fn set_stereo_mode(&self, stereo_mode: StereoMode);
    fn set_viewport(&self, x: f32, y: f32, width: f32, height: f32);
    fn transform(&self, matrix: &Matrix);
    fn translate(&self, x: f32, y: f32, z: f32);
}

Trait containing all Framebuffer methods.

Implementors

Framebuffer, Onscreen

Required Methods

fn add_fence_callback<P: Fn(&Fence) + 'static>( &self, callback: P, ) -> Option<FenceClosure>

Calls the provided callback when all previously-submitted commands have been executed by the GPU.

Returns non-NULL if the fence succeeded, or None if it was unable to be inserted and the callback will never be called. The user does not need to free the closure; it will be freed automatically when the callback is called, or cancelled.

callback

A CoglFenceCallback to be called when all commands submitted to Cogl have been executed

user_data

Private data that will be passed to the callback

fn allocate(&self) -> Result<bool, Error>

Explicitly allocates a configured Framebuffer allowing developers to check and handle any errors that might arise from an unsupported configuration so that fallback configurations may be tried.

<note>Many applications don’t support any fallback options at least when they are initially developed and in that case the don’t need to use this API since Cogl will automatically allocate a framebuffer when it first gets used. The disadvantage of relying on automatic allocation is that the program will abort with an error message if there is an error during automatic allocation.</note>

Returns

true if there were no error allocating the framebuffer, else false.

fn cancel_fence_callback(&self, closure: &mut FenceClosure)

Removes a fence previously submitted with Framebuffer::add_fence_callback; the callback will not be called.

closure

The FenceClosure returned from Framebuffer::add_fence_callback

fn clear(&self, buffers: c_ulong, color: &Color)

Clears all the auxiliary buffers identified in the buffers mask, and if that includes the color buffer then the specified color is used.

buffers

A mask of BufferBit’s identifying which auxiliary buffers to clear

color

The color to clear the color buffer too if specified in buffers.

fn clear4f(&self, buffers: c_ulong, red: f32, green: f32, blue: f32, alpha: f32)

Clears all the auxiliary buffers identified in the buffers mask, and if that includes the color buffer then the specified color is used.

buffers

A mask of BufferBit’s identifying which auxiliary buffers to clear

red

The red component of color to clear the color buffer too if specified in buffers.

green

The green component of color to clear the color buffer too if specified in buffers.

blue

The blue component of color to clear the color buffer too if specified in buffers.

alpha

The alpha component of color to clear the color buffer too if specified in buffers.

fn discard_buffers(&self, buffers: c_ulong)

Declares that the specified buffers no longer need to be referenced by any further rendering commands. This can be an important optimization to avoid subsequent frames of rendering depending on the results of a previous frame.

For example; some tile-based rendering GPUs are able to avoid allocating and accessing system memory for the depth and stencil buffer so long as these buffers are not required as input for subsequent frames and that can save a significant amount of memory bandwidth used to save and restore their contents to system memory between frames.

It is currently considered an error to try and explicitly discard the color buffer by passing BufferBit::Color. This is because the color buffer is already implicitly discard when you finish rendering to a Onscreen framebuffer, and it’s not meaningful to try and discard the color buffer of a CoglOffscreen framebuffer since they are single-buffered.

buffers

A BufferBit mask of which ancillary buffers you want to discard.

fn draw_multitextured_rectangle( &self, pipeline: &Pipeline, x_1: f32, y_1: f32, x_2: f32, y_2: f32, tex_coords: &[f32], )

Draws a textured rectangle to self with the given pipeline state with the top left corner positioned at (x_1, y_1) and the bottom right corner positioned at (x_2, y_2). As a pipeline may contain multiple texture layers this interface lets you supply texture coordinates for each layer of the pipeline.

<note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note>

This is a high level drawing api that can handle any kind of MetaTexture texture for the first layer such as Texture2DSliced textures which may internally be comprised of multiple low-level textures. This is unlike low-level drawing apis such as Primitive::draw which only support low level texture types that are directly supported by GPUs such as Texture2D.

<note>This api can not currently handle multiple high-level meta texture layers. The first layer may be a high level meta texture such as Texture2DSliced but all other layers much be low level textures such as Texture2D and additionally they should be textures that can be sampled using normalized coordinates (so not TextureRectangle textures).</note>

The top left texture coordinate for layer 0 of any pipeline will be (tex_coords[0], tex_coords[1]) and the bottom right coordinate will be (tex_coords[2], tex_coords[3]). The coordinates for layer 1 would be (tex_coords[4], tex_coords[5]) (tex_coords[6], tex_coords[7]) and so on…

The given texture coordinates should always be normalized such that (0, 0) corresponds to the top left and (1, 1) corresponds to the bottom right. To map an entire texture across the rectangle pass in tex_coords[0]=0, tex_coords[1]=0, tex_coords[2]=1, tex_coords[3]=1.

<note>Even if you have associated a TextureRectangle texture which normally implies working with non-normalized texture coordinates this api should still be passed normalized texture coordinates.</note>

The first pair of coordinates are for the first layer (with the smallest layer index) and if you supply less texture coordinates than there are layers in the current source material then default texture coordinates (0.0, 0.0, 1.0, 1.0) are generated.

pipeline

A Pipeline state object

x_1

x coordinate upper left on screen.

y_1

y coordinate upper left on screen.

x_2

x coordinate lower right on screen.

y_2

y coordinate lower right on screen.

tex_coords

An array containing groups of 4 float values: [s_1, t_1, s_2, t_2] that are interpreted as two texture coordinates; one for the top left texel, and one for the bottom right texel. Each value should be between 0.0 and 1.0, where the coordinate (0.0, 0.0) represents the top left of the texture, and (1.0, 1.0) the bottom right.

tex_coords_len

The length of the tex_coords array. (For one layer and one group of texture coordinates, this would be 4)

fn draw_rectangle( &self, pipeline: &Pipeline, x_1: f32, y_1: f32, x_2: f32, y_2: f32, )

Draws a rectangle to self with the given pipeline state and with the top left corner positioned at (x_1, y_1) and the bottom right corner positioned at (x_2, y_2).

<note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note>

<note>If you want to describe a rectangle with a texture mapped on it then you can use Framebuffer::draw_textured_rectangle.</note>

pipeline

A Pipeline state object

x_1

X coordinate of the top-left corner

y_1

Y coordinate of the top-left corner

x_2

X coordinate of the bottom-right corner

y_2

Y coordinate of the bottom-right corner

fn draw_textured_rectangle( &self, pipeline: &Pipeline, x_1: f32, y_1: f32, x_2: f32, y_2: f32, s_1: f32, t_1: f32, s_2: f32, t_2: f32, )

Draws a textured rectangle to self using the given pipeline state with the top left corner positioned at (x_1, y_1) and the bottom right corner positioned at (x_2, y_2). The top left corner will have texture coordinates of (s_1, t_1) and the bottom right corner will have texture coordinates of (s_2, t_2).

<note>The position is the position before the rectangle has been transformed by the model-view matrix and the projection matrix.</note>

This is a high level drawing api that can handle any kind of MetaTexture texture such as Texture2DSliced textures which may internally be comprised of multiple low-level textures. This is unlike low-level drawing apis such as Primitive::draw which only support low level texture types that are directly supported by GPUs such as Texture2D.

<note>The given texture coordinates will only be used for the first texture layer of the pipeline and if your pipeline has more than one layer then all other layers will have default texture coordinates of s_1=0.0 t_1=0.0 s_2=1.0 t_2=1.0 </note>

The given texture coordinates should always be normalized such that (0, 0) corresponds to the top left and (1, 1) corresponds to the bottom right. To map an entire texture across the rectangle pass in s_1=0, t_1=0, s_2=1, t_2=1.

<note>Even if you have associated a TextureRectangle texture with one of your pipeline layers which normally implies working with non-normalized texture coordinates this api should still be passed normalized texture coordinates.</note>

pipeline

A Pipeline state object

x_1

x coordinate upper left on screen.

y_1

y coordinate upper left on screen.

x_2

x coordinate lower right on screen.

y_2

y coordinate lower right on screen.

s_1

S texture coordinate of the top-left coorner

t_1

T texture coordinate of the top-left coorner

s_2

S texture coordinate of the bottom-right coorner

t_2

T texture coordinate of the bottom-right coorner

fn finish(&self)

This blocks the CPU until all pending rendering associated with the specified framebuffer has completed. It’s very rare that developers should ever need this level of synchronization with the GPU and should never be used unless you clearly understand why you need to explicitly force synchronization.

One example might be for benchmarking purposes to be sure timing measurements reflect the time that the GPU is busy for not just the time it takes to queue rendering commands.

fn frustum( &self, left: f32, right: f32, bottom: f32, top: f32, z_near: f32, z_far: f32, )

Replaces the current projection matrix with a perspective matrix for a given viewing frustum defined by 4 side clip planes that all cross through the origin and 2 near and far clip planes.

left

X position of the left clipping plane where it intersects the near clipping plane

right

X position of the right clipping plane where it intersects the near clipping plane

bottom

Y position of the bottom clipping plane where it intersects the near clipping plane

top

Y position of the top clipping plane where it intersects the near clipping plane

z_near

The distance to the near clipping plane (Must be positive)

z_far

The distance to the far clipping plane (Must be positive)

fn get_alpha_bits(&self) -> i32

Retrieves the number of alpha bits of self

Returns

the number of bits

fn get_blue_bits(&self) -> i32

Retrieves the number of blue bits of self

Returns

the number of bits

fn get_color_mask(&self) -> ColorMask

Gets the current ColorMask of which channels would be written to the current framebuffer. Each bit set in the mask means that the corresponding color would be written.

Returns

A ColorMask

fn get_context(&self) -> Option<Context>

Can be used to query the Context a given self was instantiated within. This is the Context that was passed to Onscreen::new for example.

Returns

The Context that the given self was instantiated within.

fn get_depth_bits(&self) -> i32

Retrieves the number of depth bits of self

Returns

the number of bits

fn get_depth_texture(&self) -> Option<Texture>

Retrieves the depth buffer of self as a Texture. You need to call cogl_framebuffer_get_depth_texture(fb, TRUE); before using this function.

<note>Calling this function implicitely allocates the framebuffer.</note> <note>The texture returned stays valid as long as the framebuffer stays valid.</note>

Returns

the depth texture

fn get_depth_texture_enabled(&self) -> bool

Queries whether texture based depth buffer has been enabled via Framebuffer::set_depth_texture_enabled.

Returns

true if a depth texture has been enabled, else false.

fn get_depth_write_enabled(&self) -> bool

Queries whether depth buffer writing is enabled for self. This can be controlled via Framebuffer::set_depth_write_enabled.

Returns

true if depth writing is enabled or false if not.

fn get_dither_enabled(&self) -> bool

Returns whether dithering has been requested for the given self. See Framebuffer::set_dither_enabled for more details about dithering.

<note>This may return true even when the underlying self display pipeline does not support dithering. This value only represents the user’s request for dithering.</note>

Returns

true if dithering has been requested or false if not.

fn get_green_bits(&self) -> i32

Retrieves the number of green bits of self

Returns

the number of bits

fn get_height(&self) -> i32

Queries the current height of the given self.

Returns

The height of self.

fn get_is_stereo(&self) -> bool

fn get_modelview_matrix(&self) -> Matrix

Stores the current model-view matrix in matrix.

matrix

return location for the model-view matrix

fn get_projection_matrix(&self) -> Matrix

Stores the current projection matrix in matrix.

matrix

return location for the projection matrix

fn get_red_bits(&self) -> i32

Retrieves the number of red bits of self

Returns

the number of bits

fn get_samples_per_pixel(&self) -> i32

Gets the number of points that are sampled per-pixel when rasterizing geometry. Usually by default this will return 0 which means that single-sample not multisample rendering has been chosen. When using a GPU supporting multisample rendering it’s possible to increase the number of samples per pixel using Framebuffer::set_samples_per_pixel.

Calling Framebuffer::get_samples_per_pixel before the framebuffer has been allocated will simply return the value set using Framebuffer::set_samples_per_pixel. After the framebuffer has been allocated the value will reflect the actual number of samples that will be made by the GPU.

Returns

The number of point samples made per pixel when rasterizing geometry or 0 if single-sample rendering has been chosen.

fn get_stereo_mode(&self) -> StereoMode

Gets the current StereoMode, which defines which stereo buffers should be drawn to. See Framebuffer::set_stereo_mode.

Returns

A StereoMode

fn get_viewport_height(&self) -> f32

Queries the height of the viewport as set using Framebuffer::set_viewport or the default value which is the height of the framebuffer.

Returns

The height of the viewport.

fn get_viewport_width(&self) -> f32

Queries the width of the viewport as set using Framebuffer::set_viewport or the default value which is the width of the framebuffer.

Returns

The width of the viewport.

fn get_viewport_x(&self) -> f32

Queries the x coordinate of the viewport origin as set using Framebuffer::set_viewport or the default value which is 0.

Returns

The x coordinate of the viewport origin.

fn get_viewport_y(&self) -> f32

Queries the y coordinate of the viewport origin as set using Framebuffer::set_viewport or the default value which is 0.

Returns

The y coordinate of the viewport origin.

fn get_width(&self) -> i32

Queries the current width of the given self.

Returns

The width of self.

fn identity_matrix(&self)

Resets the current model-view matrix to the identity matrix.

fn orthographic( &self, x_1: f32, y_1: f32, x_2: f32, y_2: f32, near: f32, far: f32, )

Replaces the current projection matrix with an orthographic projection matrix.

x_1

The x coordinate for the first vertical clipping plane

y_1

The y coordinate for the first horizontal clipping plane

x_2

The x coordinate for the second vertical clipping plane

y_2

The y coordinate for the second horizontal clipping plane

near

The <emphasis>distance</emphasis> to the near clipping plane (will be <emphasis>negative</emphasis> if the plane is behind the viewer)

far

The <emphasis>distance</emphasis> to the far clipping plane (will be <emphasis>negative</emphasis> if the plane is behind the viewer)

fn perspective(&self, fov_y: f32, aspect: f32, z_near: f32, z_far: f32)

Replaces the current projection matrix with a perspective matrix based on the provided values.

<note>You should be careful not to have to great a z_far / z_near ratio since that will reduce the effectiveness of depth testing since there wont be enough precision to identify the depth of objects near to each other.</note>

fov_y

Vertical field of view angle in degrees.

aspect

The (width over height) aspect ratio for display

z_near

The distance to the near clipping plane (Must be positive, and must not be 0)

z_far

The distance to the far clipping plane (Must be positive)

fn pop_clip(&self)

Reverts the clipping region to the state before the last call to Framebuffer::push_scissor_clip, Framebuffer::push_rectangle_clip cogl_framebuffer_push_path_clip, or Framebuffer::push_primitive_clip.

fn pop_matrix(&self)

Restores the model-view matrix on the top of the matrix stack.

fn push_matrix(&self)

Copies the current model-view matrix onto the matrix stack. The matrix can later be restored with Framebuffer::pop_matrix.

fn push_primitive_clip( &self, primitive: &Primitive, bounds_x1: f32, bounds_y1: f32, bounds_x2: f32, bounds_y2: f32, )

Sets a new clipping area using a 2D shaped described with a Primitive. The shape must not contain self overlapping geometry and must lie on a single 2D plane. A bounding box of the 2D shape in local coordinates (the same coordinates used to describe the shape) must be given. It is acceptable for the bounds to be larger than the true bounds but behaviour is undefined if the bounds are smaller than the true bounds.

The primitive is transformed by the current model-view matrix and the silhouette is intersected with the previous clipping area. To restore the previous clipping area, call Framebuffer::pop_clip.

primitive

A Primitive describing a flat 2D shape

bounds_x1

x coordinate for the top-left corner of the primitives bounds

bounds_y1

y coordinate for the top-left corner of the primitives bounds

bounds_x2

x coordinate for the bottom-right corner of the primitives bounds.

bounds_y2

y coordinate for the bottom-right corner of the primitives bounds.

fn push_rectangle_clip(&self, x_1: f32, y_1: f32, x_2: f32, y_2: f32)

Specifies a modelview transformed rectangular clipping area for all subsequent drawing operations. Any drawing commands that extend outside the rectangle will be clipped so that only the portion inside the rectangle will be displayed. The rectangle dimensions are transformed by the current model-view matrix.

The rectangle is intersected with the current clip region. To undo the effect of this function, call Framebuffer::pop_clip.

x_1

x coordinate for top left corner of the clip rectangle

y_1

y coordinate for top left corner of the clip rectangle

x_2

x coordinate for bottom right corner of the clip rectangle

y_2

y coordinate for bottom right corner of the clip rectangle

fn push_scissor_clip(&self, x: i32, y: i32, width: i32, height: i32)

Specifies a rectangular clipping area for all subsequent drawing operations. Any drawing commands that extend outside the rectangle will be clipped so that only the portion inside the rectangle will be displayed. The rectangle dimensions are not transformed by the current model-view matrix.

The rectangle is intersected with the current clip region. To undo the effect of this function, call Framebuffer::pop_clip.

x

left edge of the clip rectangle in window coordinates

y

top edge of the clip rectangle in window coordinates

width

width of the clip rectangle

height

height of the clip rectangle

fn read_pixels( &self, x: i32, y: i32, width: i32, height: i32, format: PixelFormat, pixels: &[u8], ) -> bool

This is a convenience wrapper around Framebuffer::read_pixels_into_bitmap which allocates a temporary Bitmap to read pixel data directly into the given buffer. The rowstride of the buffer is assumed to be the width of the region times the bytes per pixel of the format. The source for the data is always taken from the color buffer. If you want to use any other rowstride or source, please use the Framebuffer::read_pixels_into_bitmap function directly.

The implementation of the function looks like this:

bitmap = cogl_bitmap_new_for_data (context,
                                   width, height,
                                   format,
                                   /<!-- -->* rowstride *<!-- -->/
                                   bpp * width,
                                   pixels);
cogl_framebuffer_read_pixels_into_bitmap (framebuffer,
                                          x, y,
                                          COGL_READ_PIXELS_COLOR_BUFFER,
                                          bitmap);
cogl_object_unref (bitmap);

x

The x position to read from

y

The y position to read from

width

The width of the region of rectangles to read

height

The height of the region of rectangles to read

format

The pixel format to store the data in

pixels

The address of the buffer to store the data in

Returns

true if the read succeeded or false otherwise.

fn read_pixels_into_bitmap( &self, x: i32, y: i32, source: ReadPixelsFlags, bitmap: &Bitmap, ) -> bool

This reads a rectangle of pixels from the given framebuffer where position (0, 0) is the top left. The pixel at (x, y) is the first read, and a rectangle of pixels with the same size as the bitmap is read right and downwards from that point.

Currently Cogl assumes that the framebuffer is in a premultiplied format so if the format of bitmap is non-premultiplied it will convert it. To read the pixel values without any conversion you should either specify a format that doesn’t use an alpha channel or use one of the formats ending in PRE.

x

The x position to read from

y

The y position to read from

source

Identifies which auxillary buffer you want to read (only COGL_READ_PIXELS_COLOR_BUFFER supported currently)

bitmap

The bitmap to store the results in.

Returns

true if the read succeeded or false otherwise. The function is only likely to fail if the bitmap points to a pixel buffer and it could not be mapped.

fn resolve_samples(&self)

When point sample rendering (also known as multisample rendering) has been enabled via Framebuffer::set_samples_per_pixel then you can optionally call this function (or Framebuffer::resolve_samples_region) to explicitly resolve the point samples into values for the final color buffer.

Some GPUs will implicitly resolve the point samples during rendering and so this function is effectively a nop, but with other architectures it is desirable to defer the resolve step until the end of the frame.

Since Cogl will automatically ensure samples are resolved if the target color buffer is used as a source this API only needs to be used if explicit control is desired - perhaps because you want to ensure that the resolve is completed in advance to avoid later having to wait for the resolve to complete.

If you are performing incremental updates to a framebuffer you should consider using Framebuffer::resolve_samples_region instead to avoid resolving redundant pixels.

fn resolve_samples_region(&self, x: i32, y: i32, width: i32, height: i32)

When point sample rendering (also known as multisample rendering) has been enabled via Framebuffer::set_samples_per_pixel then you can optionally call this function (or Framebuffer::resolve_samples) to explicitly resolve the point samples into values for the final color buffer.

Some GPUs will implicitly resolve the point samples during rendering and so this function is effectively a nop, but with other architectures it is desirable to defer the resolve step until the end of the frame.

Use of this API is recommended if incremental, small updates to a framebuffer are being made because by default Cogl will implicitly resolve all the point samples of the framebuffer which can result in redundant work if only a small number of samples have changed.

Because some GPUs implicitly resolve point samples this function only guarantees that at-least the region specified will be resolved and if you have rendered to a larger region then it’s possible that other samples may be implicitly resolved.

x

top-left x coordinate of region to resolve

y

top-left y coordinate of region to resolve

width

width of region to resolve

height

height of region to resolve

fn rotate(&self, angle: f32, x: f32, y: f32, z: f32)

Multiplies the current model-view matrix by one that rotates the model around the axis-vector specified by x, y and z. The rotation follows the right-hand thumb rule so for example rotating by 10 degrees about the axis-vector (0, 0, 1) causes a small counter-clockwise rotation.

angle

Angle in degrees to rotate.

x

X-component of vertex to rotate around.

y

Y-component of vertex to rotate around.

z

Z-component of vertex to rotate around.

fn rotate_euler(&self, euler: &Euler)

Multiplies the current model-view matrix by one that rotates according to the rotation described by euler.

euler

A Euler

fn rotate_quaternion(&self, quaternion: &Quaternion)

Multiplies the current model-view matrix by one that rotates according to the rotation described by quaternion.

quaternion

A Quaternion

fn scale(&self, x: f32, y: f32, z: f32)

Multiplies the current model-view matrix by one that scales the x, y and z axes by the given values.

x

Amount to scale along the x-axis

y

Amount to scale along the y-axis

z

Amount to scale along the z-axis

fn set_color_mask(&self, color_mask: ColorMask)

Defines a bit mask of which color channels should be written to the given self. If a bit is set in color_mask that means that color will be written.

color_mask

A ColorMask of which color channels to write to the current framebuffer.

fn set_depth_texture_enabled(&self, enabled: bool)

If enabled is true, the depth buffer used when rendering to self is available as a texture. You can retrieve the texture with Framebuffer::get_depth_texture.

<note>It’s possible that your GPU does not support depth textures. You should check the FeatureID::OglFeatureIdDepthTexture feature before using this function.</note> <note>It’s not valid to call this function after the framebuffer has been allocated as the creation of the depth texture is done at allocation time. </note>

enabled

TRUE or FALSE

fn set_depth_write_enabled(&self, depth_write_enabled: bool)

Enables or disables depth buffer writing when rendering to self. If depth writing is enabled for both the framebuffer and the rendering pipeline, and the framebuffer has an associated depth buffer, depth information will be written to this buffer during rendering.

Depth buffer writing is enabled by default.

depth_write_enabled

true to enable depth writing or false to disable

fn set_dither_enabled(&self, dither_enabled: bool)

Enables or disabled dithering if supported by the hardware.

Dithering is a hardware dependent technique to increase the visible color resolution beyond what the underlying hardware supports by playing tricks with the colors placed into the framebuffer to give the illusion of other colors. (For example this can be compared to half-toning used by some news papers to show varying levels of grey even though their may only be black and white are available).

If the current display pipeline for self does not support dithering then this has no affect.

Dithering is enabled by default.

dither_enabled

true to enable dithering or false to disable

fn set_modelview_matrix(&self, matrix: &Matrix)

Sets matrix as the new model-view matrix.

matrix

the new model-view matrix

fn set_projection_matrix(&self, matrix: &Matrix)

Sets matrix as the new projection matrix.

matrix

the new projection matrix

fn set_samples_per_pixel(&self, samples_per_pixel: i32)

Requires that when rendering to self then n point samples should be made per pixel which will all contribute to the final resolved color for that pixel. The idea is that the hardware aims to get quality similar to what you would get if you rendered everything twice as big (for 4 samples per pixel) and then scaled that image back down with filtering. It can effectively remove the jagged edges of polygons and should be more efficient than if you were to manually render at a higher resolution and downscale because the hardware is often able to take some shortcuts. For example the GPU may only calculate a single texture sample for all points of a single pixel, and for tile based architectures all the extra sample data (such as depth and stencil samples) may be handled on-chip and so avoid increased demand on system memory bandwidth.

By default this value is usually set to 0 and that is referred to as “single-sample” rendering. A value of 1 or greater is referred to as “multisample” rendering.

<note>There are some semantic differences between single-sample rendering and multisampling with just 1 point sample such as it being redundant to use the Framebuffer::resolve_samples and Framebuffer::resolve_samples_region apis with single-sample rendering.</note>

<note>It’s recommended that Framebuffer::resolve_samples_region be explicitly used at the end of rendering to a point sample buffer to minimize the number of samples that get resolved. By default Cogl will implicitly resolve all framebuffer samples but if only a small region of a framebuffer has changed this can lead to redundant work being done.</note>

samples_per_pixel

The minimum number of samples per pixel

fn set_stereo_mode(&self, stereo_mode: StereoMode)

Sets which stereo buffers should be drawn to. The default is StereoMode::Both, which means that both the left and right buffers will be affected by drawing. For this to have an effect, the display system must support stereo drawables, and the framebuffer must have been created with stereo enabled. (See OnscreenTemplate::set_stereo_enabled, Framebuffer::get_is_stereo.)

stereo_mode

A StereoMode specifying which stereo buffers should be drawn tow.

fn set_viewport(&self, x: f32, y: f32, width: f32, height: f32)

Defines a scale and offset for everything rendered relative to the top-left of the destination framebuffer.

By default the viewport has an origin of (0,0) and width and height that match the framebuffer’s size. Assuming a default projection and modelview matrix then you could translate the contents of a window down and right by leaving the viewport size unchanged by moving the offset to (10,10). The viewport coordinates are measured in pixels. If you left the x and y origin as (0,0) you could scale the windows contents down by specify and width and height that’s half the real size of the framebuffer.

<note>Although the function takes floating point arguments, existing drivers only allow the use of integer values. In the future floating point values will be exposed via a checkable feature.</note>

x

The top-left x coordinate of the viewport origin (only integers supported currently)

y

The top-left y coordinate of the viewport origin (only integers supported currently)

width

The width of the viewport (only integers supported currently)

height

The height of the viewport (only integers supported currently)

fn transform(&self, matrix: &Matrix)

Multiplies the current model-view matrix by the given matrix.

matrix

the matrix to multiply with the current model-view

fn translate(&self, x: f32, y: f32, z: f32)

Multiplies the current model-view matrix by one that translates the model along all three axes according to the given values.

x

Distance to translate along the x-axis

y

Distance to translate along the y-axis

z

Distance to translate along the z-axis

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<O: IsA<Framebuffer>> FramebufferExt for O