Draws triangles in an image. More...

#include <geogram/image/image_rasterizer.h>

Public Member Functions
	ImageRasterizer (Image *image)
	ImageRasterizer constructor. More...

void	clear ()
	Clears the target image.

void	triangle (const vec2i &P1, const Color &c1, const vec2i &P2, const Color &c2, const vec2i &P3, const Color &c3)
	Draws a triangle in the target image. More...

void	triangle (const vec2 &p1, const Color &c1, const vec2 &p2, const Color &c2, const vec2 &p3, const Color &c3)
	Draws a triangle in the target image. More...

void	segment (const vec2i &P1, const vec2i &P2, const Color &c)
	Draws a segment in the target image. More...

void	segment (const vec2 &p1, const vec2 &p2, const Color &c)
	Draws a segment in the target image. More...

void	fillcircle (const vec2i &C, int radius, const Color &c)
	Fills a circle in the target image. More...

void	fillcircle (const vec2 &C, double radius, const Color &c)
	Fills a circle in the target image. More...

void	flood_fill (int x, int y, const Color &c)
	Flood-fill from a given pixel. More...

void	set_pixel (int x, int y, const Color &c)
	Sets a pixel of the image. More...

bool	pixel_is_black (int x, int y) const
	Tests whether a given pixel is black. More...

Protected Member Functions
vec2i	transform (const vec2 &p) const
	Transforms a 2d point from world space to pixel coordinates. More...

void	interpolate_color (const Color &c1, const Color &c2, const Color &c3, double l1, double l2, double l3, Color &c) const
	Computes the linear interpolation between three colors. More...

Detailed Description

Draws triangles in an image.

Definition at line 56 of file image_rasterizer.h.

Constructor & Destructor Documentation

◆ ImageRasterizer()

GEO::ImageRasterizer::ImageRasterizer ( Image * image )

ImageRasterizer constructor.

Parameters

[in] image a pointer to the target image.

Member Function Documentation

◆ fillcircle() [1/2]

void GEO::ImageRasterizer::fillcircle	(	const vec2 &	C,
		double	radius,
		const Color &	c
	)

inline

Fills a circle in the target image.

The circle is clipped to the image

Parameters

[in]	C	the center of the circle, coordinates are between 0.0 and 1.0.
[in]	radius	the radius of the circle. A value of 1.0 corresponds to the width of the image.
[in]	c	the color of the pixels

Definition at line 151 of file image_rasterizer.h.

◆ fillcircle() [2/2]

void GEO::ImageRasterizer::fillcircle	(	const vec2i &	C,
		int	radius,
		const Color &	c
	)

Fills a circle in the target image.

The circle is clipped to the image

Parameters

[in]	C	the center of the circle, integer coordinates are in [0..width-1]x[0..height-1], where width and height are the sizes of the target image.
[in]	radius	the radius of the circle (in pixels).
[in]	c	the color of the pixels

◆ flood_fill()

void GEO::ImageRasterizer::flood_fill	(	int	x,
		int	y,
		const Color &	c
	)

Flood-fill from a given pixel.

Fills the connected component of black (zero) pixels incident to x,y

◆ interpolate_color()

void GEO::ImageRasterizer::interpolate_color	(	const Color &	c1,
		const Color &	c2,
		const Color &	c3,
		double	l1,
		double	l2,
		double	l3,
		Color &	c
	)		const

inlineprotected

Computes the linear interpolation between three colors.

Parameters

[in]	c1,c2,c3	the three colors to be interpolated.
[in]	l1,l2,l3	the coefficients of the interpolation.
[out]	c	the interpolated color.

Definition at line 250 of file image_rasterizer.h.

◆ pixel_is_black()

bool GEO::ImageRasterizer::pixel_is_black	(	int	x,
		int	y
	)		const

inline

Tests whether a given pixel is black.

Only implemented for BYTE component encoding

Parameters

[in] x,y the integer coordinates of the pixel

Return values

true	if the pixel is black
false	otherwise

Definition at line 219 of file image_rasterizer.h.

◆ segment() [1/2]

void GEO::ImageRasterizer::segment	(	const vec2 &	p1,
		const vec2 &	p2,
		const Color &	c
	)

inline

Draws a segment in the target image.

No clipping is done. It is the responsibility of the caller to give valid coordinates.

Parameters

[in]	p1,p2	the two extremities of the segment. coordinates are in the [0,1]x[0,1] square.
[in]	c	the color

Definition at line 127 of file image_rasterizer.h.

◆ segment() [2/2]

void GEO::ImageRasterizer::segment	(	const vec2i &	P1,
		const vec2i &	P2,
		const Color &	c
	)

Draws a segment in the target image.

No clipping is done. It is the responsibility of the caller to give valid coordinates.

Parameters

[in]	P1,P2	the two extremities of the segment. integer coordinates are in [0..width-1]x[0..height-1], where width and height are the sizes of the target image.
[in]	c	the color

◆ set_pixel()

void GEO::ImageRasterizer::set_pixel	(	int	x,
		int	y,
		const Color &	c
	)

inline

Sets a pixel of the image.

Only BYTE, FLOAT32 and FLOAT64 component encoding are supported. If the image has less than 4 channels, the extra channels in c are ignored.

Parameters

[in]	x,y	the integer pixel coordinates
[in]	c	the color of the pixel

Definition at line 174 of file image_rasterizer.h.

◆ transform()

vec2i GEO::ImageRasterizer::transform ( const vec2 & p ) const

inlineprotected

Transforms a 2d point from world space to pixel coordinates.

Parameters

[in] p coordinates of the points, in [0,1]x[0,1]

Returns: transformed the pixel coordinates of the point.

Definition at line 237 of file image_rasterizer.h.

◆ triangle() [1/2]

void GEO::ImageRasterizer::triangle	(	const vec2 &	p1,
		const Color &	c1,
		const vec2 &	p2,
		const Color &	c2,
		const vec2 &	p3,
		const Color &	c3
	)

inline

Draws a triangle in the target image.

Colors are linearly interpolated (Gouraud shading). No clipping is done. It is the responsibility of the caller to give coordinates in the viewport.

Parameters

[in]	p1,p2,p3	the three vertices of the triangle, coordinates are in the [0,1]x[0,1] square.
[in]	c1,c2,c3	the three colors of the vertices.

Definition at line 96 of file image_rasterizer.h.

◆ triangle() [2/2]

void GEO::ImageRasterizer::triangle	(	const vec2i &	P1,
		const Color &	c1,
		const vec2i &	P2,
		const Color &	c2,
		const vec2i &	P3,
		const Color &	c3
	)

Draws a triangle in the target image.

Colors are linearly interpolated (Gouraud shading). No clipping is done. It is the responsibility of the caller to give coordinates in the viewport.

Parameters

[in]	P1,P2,P3	the three vertices of the triangle, integer coordinates are in [0..width-1]x[0..height-1], where width and height are the sizes of the target image.
[in]	c1,c2,c3	the three colors of the vertices.

The documentation for this class was generated from the following file:

geogram/image/image_rasterizer.h

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ImageRasterizer()

Member Function Documentation

◆ fillcircle() [1/2]

◆ fillcircle() [2/2]

◆ flood_fill()

◆ interpolate_color()

◆ pixel_is_black()

◆ segment() [1/2]

◆ segment() [2/2]

◆ set_pixel()

◆ transform()

◆ triangle() [1/2]

◆ triangle() [2/2]