Some basic drawing functionalities (2D/3D). More...

Classes
class	ArrowParams
	Arrow parameters passed to DrawArrow. More...
struct	Vertex
	The vertex type used by DrawHelpers (V4F_C4F) More...
Public Member Functions
	DrawHelpers (GraphicsContextAlpha gl, uint max_vertices)
void	Dispose ()
	Dispose implementation.
void	ImmBegin (DrawMode mode, uint max_vertices_intended)
	Start a new immediate primitive.
void	ImmVertex (Vertex v)
	Add a vertex to current primitive.
void	ImmVertex (Vector4 pos)
	Add a vertex to current primitive, using the most recent color set by SetColor().
void	ImmVertex (Vector2 pos)
	Add a vertex to current primitive, using the most recent color set by SetColor().
void	ImmEnd ()
	Finish current primitive (this function triggers the actual draw call).
void	ShaderPush ()
	ShaderPush() reads current MVP matrix and sets the current shader.
void	ShaderPop ()
	"Pop" the shader.
void	SetColor (Vector4 value)
	Set the color to be used by the next calls to ImmVertex.
void	DrawBounds2Fill (Bounds2 bounds)
	Draw a filled axis aligned rectangle.
void	DrawBounds2 (Bounds2 bounds)
	Draw a wireframe axis aligned rectangle.
void	DrawConvexPoly2 (ConvexPoly2 convex_poly)
	Draw convex polygon.
void	DrawDisk (Vector2 center, float radius, uint n)
	Draw a filled disk.
void	DrawCircle (Vector2 center, float radius, uint n)
	Draw a filled circle.
void	DrawCoordinateSystem2D (Matrix3 mat, ArrowParams ap=null)
	Draw the coordinate system represented by a transformation matrix using arrows.
void	DrawCoordinateSystem2D ()
	Draw a unit len arrow on x and y axis.
void	DrawArrow (Vector2 start_point, Vector2 end_point, ArrowParams ap)
	Draw a 2d arrow.
void	DrawLineSegment (Vector2 A, Vector2 B)
	Draw a single line segment.
void	DrawInfiniteLine (Vector2 A, Vector2 v)
	Draw a single line segment.
void	DrawRulers (Bounds2 bounds, float step_x, float step_y)
	Draw all the vertical and horizontal lines in a given rectangle, regularly spaced.
void	DrawAxis (Bounds2 clipping_bounds, float thickness)
	Draw axis lines (x=0 and y=0 lines) with a thickness.
void	DrawDefaultGrid (Bounds2 clipping_bounds, Vector2 step, Vector4 rulers_color, Vector4 axis_color)
	This function draws all the vertical and horizontal lines (rulers) regularly placed at multiples of 'step' distances that are inside the rectangle 'clipping_bounds'.
void	DrawDefaultGrid (Bounds2 clipping_bounds, float step)
	DrawDefaultGrid with a default color/blend.
Properties
bool	Disposed `[get]`
	Return true if this object been disposed.

Detailed Description

Some basic drawing functionalities (2D/3D).

This class is mostly an ImmediateMode object coupled with a debug shader. You shouldn't use DrawHelpers for anything else than visual debugging, as by nature it is not performance friendly at all.

Constructor & Destructor Documentation

DrawHelpers	(	GraphicsContextAlpha	gl,
		uint	max_vertices
	)

Parameters:

gl	The core graphics context.
max_vertices	The maximum number of vertices you will be able to write in one frame with this DrawHelpers object.

Member Function Documentation

void DrawArrow	(	Vector2	start_point,
		Vector2	end_point,
		ArrowParams	ap
	)

Draw a 2d arrow.

This function can be wrapped by ImmBegin()/ImmEnd(), if you need to draw several arrows but want to limit the number of draw calls. Each arrow consumes at most 9 vertices.

Parameters:

start_point	Arrow's start point.
end_point	Arrow's tip.
ap	Arrow geometry parameters.

void DrawCircle	(	Vector2	center,
		float	radius,
		uint	n
	)

Draw a filled circle.

Parameters:

center	The center.
radius	The radius.
n	Tesselation.

void DrawCoordinateSystem2D ( )

Draw a unit len arrow on x and y axis.

Color is set to vector coordinates, so the x arrow is red (1,0,0), and the y arrow is green (0,1,0).

void DrawCoordinateSystem2D	(	Matrix3	mat,
		ArrowParams	ap = `null`
	)

Draw the coordinate system represented by a transformation matrix using arrows.

The x vector is represented by a red arrow, and the y vector is represented by a green arrow.

void DrawDefaultGrid	(	Bounds2	clipping_bounds,
		Vector2	step,
		Vector4	rulers_color,
		Vector4	axis_color
	)

This function draws all the vertical and horizontal lines (rulers) regularly placed at multiples of 'step' distances that are inside the rectangle 'clipping_bounds'.

It also draws the the 2 thick axis lines. All lines drawn are clipped again 'clipping_bounds'. Blend mode is untouched when drawing the rulers, then blend is disabled when drawing axis lines.

Parameters:

clipping_bounds	Clipping rectangle.
step	Horizontal and vertical spacing between rulers.
rulers_color	Color of rulers lines.
axis_color	Color of axis lines.

void DrawDisk	(	Vector2	center,
		float	radius,
		uint	n
	)

Draw a filled disk.

Parameters:

center	The center.
radius	The radius.
n	Tesselation.

void DrawInfiniteLine	(	Vector2	A,
		Vector2	v
	)

Draw a single line segment.

This is expensive, if you draw many lines, don't use this function.

void DrawLineSegment	(	Vector2	A,
		Vector2	B
	)

Draw a single line segment.

This is expensive, if you draw many lines, don't use this function.

void DrawRulers	(	Bounds2	bounds,
		float	step_x,
		float	step_y
	)

Draw all the vertical and horizontal lines in a given rectangle, regularly spaced.

Since the smaller step_x or step_y are, the more lines primitives are generated, it is easy to overflow the immediate draw mode vertex buffer. For that reason care must be taken when setting the step values respective to the the bounds clip area.

Parameters:

step_x	X spacing (starts at 0).
step_y	Y spacing (starts at 0).
bounds	Clipping rectangle.

void ImmBegin	(	DrawMode	mode,
		uint	max_vertices_intended
	)

Start a new immediate primitive.

Parameters:

mode	The draw primive type.
max_vertices_intended	You must specify the maximum number of vertices you intend to write with ImmVertex(): the number of ImmVertex() calls following this function must be inferior or equal to 'max_vertices_intended'.

void ImmVertex ( Vector2 pos )

Add a vertex to current primitive, using the most recent color set by SetColor().

(z,w) is set to (0,1).

void ShaderPop ( )

"Pop" the shader.

Number of ShaderPush() calls must match the number of ShaderPush().

void ShaderPush ( )

ShaderPush() reads current MVP matrix and sets the current shader.

For DrawHelpers we allow nesting (shader parameters get updated internally accordingly).

DrawHelpers Class Reference

Classes

Public Member Functions

Properties

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation