A class for the rendering graphic elements with a GL raster engine. More...

#include <thorvg.h>

Inheritance diagram for GlCanvas:

Collaboration diagram for GlCanvas:

Public Member Functions
Result	target (void display, void surface, void *context, int32_t id, uint32_t w, uint32_t h, ColorSpace cs) noexcept
	Sets the drawing target for rasterization.

Public Member Functions inherited from Canvas
const std::list< Paint * > &	paints () const noexcept
	Returns the list of paints currently held by the Canvas.

Result	push (Paint target, Paint at=nullptr) noexcept
	Adds a paint object to the root scene.

Result	remove (Paint *paint=nullptr) noexcept
	Removes a paint object or all paint objects from the root scene.

Result	update () noexcept
	Requests the canvas to update modified paint objects in preparation for rendering.

Result	draw (bool clear=false) noexcept
	Requests the canvas to render the Paint objects.

Result	viewport (int32_t x, int32_t y, int32_t w, int32_t h) noexcept
	Sets the drawing region of the canvas.

Result	sync () noexcept
	Guarantees that drawing task is finished.

Static Public Member Functions
static GlCanvas *	gen () noexcept
	Creates a new GlCanvas object.

Detailed Description

A class for the rendering graphic elements with a GL raster engine.

Member Function Documentation

static GlCanvas * gen ( )

staticnoexcept

Creates a new GlCanvas object.

noexcept

Sets the drawing target for rasterization.

This function specifies the drawing target where the rasterization will occur. It can target a specific framebuffer object (FBO) or the main surface.

Parameters

[in]	display	The platform-specific display handle (EGLDisplay for EGL). Set `nullptr` for other systems.
[in]	surface	The platform-specific surface handle (EGLSurface for EGL, HDC for WGL). Set `nullptr` for other systems.
[in]	context	The OpenGL context to be used for rendering on this canvas.
[in]	id	The GL target ID, usually indicating the FBO ID. A value of `0` specifies the main surface.
[in]	w	The width (in pixels) of the raster image.
[in]	h	The height (in pixels) of the raster image.
[in]	cs	Specifies how the pixel values should be interpreted. Currently, it only allows `ColorSpace::ABGR8888S` as `GL_RGBA8`.

Return values

Result::InsufficientCondition	If the canvas is currently rendering. Ensure that Canvas::sync() has been called before setting a new target.
Result::NonSupport	In case the gl engine is not supported.

Note: If display and surface are not provided, the ThorVG GL engine assumes that the appropriate OpenGL context is already current and will not attempt to bind a new one.