Deals with 2d collisions. More...

#include "collision.h"
#include "log.h"

Macros
#define	FX(A, B, C, x) (-(A * x + C) / B)

#define	FY(A, B, C, y) (-(B * y + C) / A)

Functions
static int	pointInPolygon (const CollPoly at, const vec2 ap, float x, float y)
	Checks whether or not a point is inside a polygon. More...

static int	LineOnPolygon (const CollPoly at, const vec2 ap, float x1, float y1, float x2, float y2, vec2 *crash)
	Checks whether or not a line intersects a polygon. More...

void	LoadPolygon (CollPoly *polygon, xmlNodePtr node)
	Loads a polygon from an xml node. More...

int	CollideSprite (const glTexture at, const int asx, const int asy, const vec2 ap, const glTexture bt, const int bsx, const int bsy, const vec2 bp, vec2 *crash)
	Checks whether or not two sprites collide. More...

int	CollideSpritePolygon (const CollPoly at, const vec2 ap, const glTexture bt, const int bsx, const int bsy, const vec2 bp, vec2 *crash)
	Checks whether or not a sprite collides with a polygon. More...

int	CollidePolygon (const CollPoly at, const vec2 ap, const CollPoly bt, const vec2 bp, vec2 *crash)
	Checks whether or not two polygons collide. /!\ The function is not symmetric: the points of polygon 2 are tested against the polygon 1. Consequently, it works better if polygon 2 is small. More...

void	RotatePolygon (CollPoly rpolygon, CollPoly ipolygon, float theta)
	Rotates a polygon. More...

int	CollideLineLine (double s1x, double s1y, double e1x, double e1y, double s2x, double s2y, double e2x, double e2y, vec2 *crash)
	Checks to see if two lines collide. More...

int	CollideLineSprite (const vec2 ap, double ad, double al, const glTexture bt, const int bsx, const int bsy, const vec2 *bp, vec2 crash[2])
	Checks to see if a line collides with a sprite. More...

int	CollideLinePolygon (const vec2 ap, double ad, double al, const CollPoly bt, const vec2 *bp, vec2 crash[2])
	Checks to see if a line collides with a polygon. More...

static int	linePointOnSegment (double d1, double x1, double y1, double x2, double y2, double x, double y)

int	CollideLineCircle (const vec2 p1, const vec2 p2, const vec2 *cc, double cr, vec2 crash[2])
	Checks to see if a line collides with a circle. More...

double	CollideCircleIntersection (const vec2 p1, double r1, const vec2 p2, double r2)

Detailed Description

Deals with 2d collisions.

Definition in file collision.c.

Macro Definition Documentation

◆ FX

#define FX	(	A,
		B,
		C,
		x
	)	(-(A * x + C) / B)

Definition at line 774 of file collision.c.

◆ FY

#define FY	(	A,
		B,
		C,
		y
	)	(-(B * y + C) / A)

Definition at line 775 of file collision.c.

Function Documentation

◆ CollideCircleIntersection()

double CollideCircleIntersection	(	const vec2 *	p1,
		double	r1,
		const vec2 *	p2,
		double	r2
	)

Definition at line 887 of file collision.c.

◆ CollideLineCircle()

int CollideLineCircle	(	const vec2 *	p1,
		const vec2 *	p2,
		const vec2 *	cc,
		double	cr,
		vec2	crash[2]
	)

Checks to see if a line collides with a circle.

Parameters

[in]	p1	Point 1 of the line segment.
[in]	p2	Point 2 of the line segment.
[in]	cc	Center of the circle.
[in]	cr	Radius of the circle.
[out]	crash	Position of the collision.

Returns: 1 on collision, 0 else.

Definition at line 786 of file collision.c.

◆ CollideLineLine()

int CollideLineLine	(	double	s1x,
		double	s1y,
		double	e1x,
		double	e1y,
		double	s2x,
		double	s2y,
		double	e2x,
		double	e2y,
		vec2 *	crash
	)

Checks to see if two lines collide.

Parameters

[in]	s1x	X start point of line 1.
[in]	s1y	Y start point of line 1.
[in]	e1x	X end point of line 1.
[in]	e1y	Y end point of line 1.
[in]	s2x	X start point of line 2.
[in]	s2y	Y start point of line 2.
[in]	e2x	X end point of line 2.
[in]	e2y	Y end point of line 2.
[out]	crash	Position of the collision.

Returns: 3 if lines are coincident, 2 if lines are parallel, 1 if lines just collide on a point, or 0 if they don't.

Definition at line 448 of file collision.c.

◆ CollideLinePolygon()

int CollideLinePolygon	(	const vec2 *	ap,
		double	ad,
		double	al,
		const CollPoly *	bt,
		const vec2 *	bp,
		vec2	crash[2]
	)

Checks to see if a line collides with a polygon.

First collisions are detected on all the walls of the polygon's rectangle. Then the collisions are tested on every line of the polygon.

Parameters

[in]	ap	Origin of the line.
[in]	ad	Direction of the line.
[in]	al	Length of the line.
[in]	bt	Polygon b.
[in]	bp	Position in space of polygon b.
[out]	crash	Position of the collision.

Returns: 1 on collision, 0 else.

See also: CollideLinePolygon

Definition at line 650 of file collision.c.

◆ CollideLineSprite()

int CollideLineSprite	(	const vec2 *	ap,
		double	ad,
		double	al,
		const glTexture *	bt,
		const int	bsx,
		const int	bsy,
		const vec2 *	bp,
		vec2	crash[2]
	)

Checks to see if a line collides with a sprite.

First collisions are detected on all the walls of the sprite's rectangle. Then the collisions are tested by pixel perfectness until collisions are actually found with the ship itself.

Parameters

[in]	ap	Origin of the line.
[in]	ad	Direction of the line.
[in]	al	Length of the line.
[in]	bt	Texture b.
[in]	bsx	Position of x of sprite b.
[in]	bsy	Position of y of sprite b.
[in]	bp	Position in space of sprite b.
[out]	crash	Position of the collision.

Returns: 1 on collision, 0 else.

See also: CollideSprite

Definition at line 501 of file collision.c.

◆ CollidePolygon()

int CollidePolygon	(	const CollPoly *	at,
		const vec2 *	ap,
		const CollPoly *	bt,
		const vec2 *	bp,
		vec2 *	crash
	)

Checks whether or not two polygons collide. /!\ The function is not symmetric: the points of polygon 2 are tested against the polygon 1. Consequently, it works better if polygon 2 is small.

Parameters

[in]	at	Polygon a.
[in]	ap	Position in space of polygon a.
[in]	bt	Polygon b.
[in]	bp	Position in space of polygon b.
[out]	crash	Actual position of the collision (only set on collision).

Returns: 1 on collision, 0 else.

Definition at line 254 of file collision.c.

◆ CollideSprite()

int CollideSprite	(	const glTexture *	at,
		const int	asx,
		const int	asy,
		const vec2 *	ap,
		const glTexture *	bt,
		const int	bsx,
		const int	bsy,
		const vec2 *	bp,
		vec2 *	crash
	)

Checks whether or not two sprites collide.

This function does pixel perfect checks. If the collision actually occurs, crash is set to store the real position of the collision.

Parameters

[in]	at	Texture a.
[in]	asx	Position of x of sprite a.
[in]	asy	Position of y of sprite a.
[in]	ap	Position in space of sprite a.
[in]	bt	Texture b.
[in]	bsx	Position of x of sprite b.
[in]	bsy	Position of y of sprite b.
[in]	bp	Position in space of sprite b.
[out]	crash	Actual position of the collision (only set on collision).

Returns: 1 on collision, 0 else.

Definition at line 97 of file collision.c.

◆ CollideSpritePolygon()

int CollideSpritePolygon	(	const CollPoly *	at,
		const vec2 *	ap,
		const glTexture *	bt,
		const int	bsx,
		const int	bsy,
		const vec2 *	bp,
		vec2 *	crash
	)

Checks whether or not a sprite collides with a polygon.

Parameters

[in]	at	Polygon a.
[in]	ap	Position in space of polygon a.
[in]	bt	Texture b.
[in]	bsx	Position of x of sprite b.
[in]	bsy	Position of y of sprite b.
[in]	bp	Position in space of sprite b.
[out]	crash	Actual position of the collision (only set on collision).

Returns: 1 on collision, 0 else.

Definition at line 179 of file collision.c.

◆ LineOnPolygon()

int LineOnPolygon	(	const CollPoly *	at,
		const vec2 *	ap,
		float	x1,
		float	y1,
		float	x2,
		float	y2,
		vec2 *	crash
	)

static

Checks whether or not a line intersects a polygon.

Parameters

[in]	at	Polygon a.
[in]	ap	Position in space of polygon a.
[in]	x1	Coordiante of point 1.
[in]	y1	Coordinate of point 1.
[in]	x2	Coordiante of point 2.
[in]	y2	Coordinate of point 2.
[out]	crash	coordinates of the intersection.

Returns: 1 on collision, 0 else.

Definition at line 408 of file collision.c.

◆ linePointOnSegment()

static int linePointOnSegment	(	double	d1,
		double	x1,
		double	y1,
		double	x2,
		double	y2,
		double	x,
		double	y
	)

static

Definition at line 766 of file collision.c.

◆ LoadPolygon()

void LoadPolygon	(	CollPoly *	polygon,
		xmlNodePtr	node
	)

Loads a polygon from an xml node.

Parameters

[out]	polygon	Polygon.
[in]	node	xml node.

Definition at line 32 of file collision.c.

◆ pointInPolygon()

int pointInPolygon	(	const CollPoly *	at,
		const vec2 *	ap,
		float	x,
		float	y
	)

static

Checks whether or not a point is inside a polygon.

Parameters

[in]	at	Polygon a.
[in]	ap	Position in space of polygon a.
[in]	x	Coordiante of point.
[in]	y	Coordinate of point.

Returns: 1 on collision, 0 else.

Definition at line 362 of file collision.c.

◆ RotatePolygon()

void RotatePolygon	(	CollPoly *	rpolygon,
		CollPoly *	ipolygon,
		float	theta
	)

Rotates a polygon.

Parameters

[out]	rpolygon	Rotated polygon.
[in]	ipolygon	Imput polygon.
[in]	theta	Rotation angle (radian).

Definition at line 325 of file collision.c.

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ FX

◆ FY

Function Documentation

◆ CollideCircleIntersection()

◆ CollideLineCircle()

◆ CollideLineLine()

◆ CollideLinePolygon()

◆ CollideLineSprite()

◆ CollidePolygon()

◆ CollideSprite()

◆ CollideSpritePolygon()

◆ LineOnPolygon()

◆ linePointOnSegment()

◆ LoadPolygon()

◆ pointInPolygon()

◆ RotatePolygon()