Helper

Source (.js)Source (.d.ts)

Methods

drawArrays

Update the shaders, bind the vertex array object and issue the draw call.

Argument	Type	Required	Description
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.
rep		Yes	The representation to draw with.
oglMapper		Yes	The OpenGL mapper driving this helper.

Returns

Type	Description
number	The number of primitives drawn.

extend

Method used to decorate a given object (publicAPI+model) with vtkOpenGLHelper characteristics.

Argument	Type	Required	Description
publicAPI		Yes	object on which methods will be bounds (public)
model		Yes	object on which data structure will be bounds (protected)
initialValues	IOpenGLHelperInitialValues	No	(default: {})

getAllocatedGPUMemoryInBytes

Get the amount of GPU memory this helper's buffers hold, in bytes.

getAttributeUpdateTime

Get the time object tracking when the attributes were last bound.

getCABO

Get the cell array buffer object holding the packed vertices.

getNeedToRebuildShaders

Whether the shader program must be rebuilt before the next draw.

Argument	Type	Required	Description
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.
oglMapper		Yes	The OpenGL mapper driving this helper.

getOpenGLMode

Get the GL draw mode for this helper's primitive, POINTS while point picking.

Argument	Type	Required	Description
rep		Yes	The representation to draw with.

getPointPicking

Whether the helper draws points for hardware point picking.

getPointPickingPrimitiveSize

Get the point size in pixels used to make this helper's primitive pickable.

getPrimitiveType

Get which of the primTypes this helper draws.

getProgram

Get the shader program this helper draws with.

getShaderSourceTime

Get the time object tracking when the shader sources were last rebuilt.

getVAO

Get the vertex array object.

haveWideLines

Whether the lines must be emulated with instanced quads because the hardware does not support the requested line width.

Argument	Type	Required	Description
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.

newInstance

Method used to create a new instance of vtkOpenGLHelper.

Argument	Type	Required	Description
initialValues	IOpenGLHelperInitialValues	No	for pre-setting some of its content

releaseGraphicsResources

Release the vertex array object and the buffers.

releasePolyDataMapperResources

Release the shared resources of a polydata mapper and invalidate its buffers.

replaceShaderPositionVC

Add the point size and, for wide lines, the line widening code to the vertex shader.

Argument	Type	Required	Description
shaders	IShaderSources	Yes	The shader sources to substitute into.
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.

setAttributeUpdateTime

Set the time object tracking when the attributes were last bound.

Argument	Type	Required	Description
attributeUpdateTime		Yes	The time object.

setCABO

Set the cell array buffer object holding the packed vertices.

Argument	Type	Required	Description
CABO		Yes	The cell array buffer object.

setMapperShaderParameters

Set the wide line and point size uniforms.

Argument	Type	Required	Description
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.
size	ITiledSizeAndOrigin	Yes	The pixel extent of the viewport.

setOpenGLRenderWindow

Attach this helper, its vertex array object and its buffers to an OpenGL render window.

Argument	Type	Required	Description
win		Yes	The OpenGL render window.

setPointPicking

Set whether the helper draws points for hardware point picking.

Argument	Type	Required	Description
pointPicking		Yes	The point picking flag.

setPrimitiveType

Set which of the primTypes this helper draws.

Argument	Type	Required	Description
primitiveType		Yes	The primitive type.

setProgram

Set the shader program this helper draws with.

Argument	Type	Required	Description
program		Yes	The shader program.

setShaderSourceTime

Set the time object tracking when the shader sources were last rebuilt.

Argument	Type	Required	Description
shaderSourceTime		Yes	The time object.

setVAO

Set the vertex array object.

Argument	Type	Required	Description
VAO		Yes	The vertex array object.

updateShaders

Rebuild the program if needed, bind it and let the mapper set its uniforms.

Argument	Type	Required	Description
ren	vtkRenderer	Yes	The renderer being drawn.
actor	vtkActor	Yes	The actor being drawn.
oglMapper		Yes	The OpenGL mapper driving this helper.