math.c File Reference

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <math.h>
#include "color.h"

Include dependency graph for math.c:

Functions
struct vec3	Vec3Init (float x, float y, float z)
void	Vec3Debug (struct vec3 v, char *name)
void	TriangleDebug (struct triangle t, char *name)
float	Vec3DotProduct (struct vec3 left, struct vec3 right)
struct vec3	Vec3CrossProduct (struct vec3 left, struct vec3 right)
struct vec3	Vec3Normalize (struct vec3 vec3)
struct vec3	Vec3Add (struct vec3 left, struct vec3 right)
struct vec3	Vec3Subtract (struct vec3 minuend, struct vec3 subtrahend)
struct vec3	Vec3Multiply (struct vec3 vec3, float f)
struct vec3	Vec3Divide (struct vec3 vec3, float f)
struct vec3	Vec3IntersectPlane (struct vec3 point, struct vec3 normal, struct vec3 lineStart, struct vec3 lineEnd, float *t)
	Return the 3d point where a line intersects a plane. More...
float	ShortestDistToPlane (struct vec3 point, struct vec3 planePoint, struct vec3 planeNormal)
	Return shortest distance from point to plan given a normalized normal.
struct triangle	TriangleInit (float x1, float y1, float z1, float u1, float v1, float x2, float y2, float z2, float u2, float v2, float x3, float y3, float z3, float u3, float v3)
	Create a new triangle with the given params.
int	TriangleClipAgainstPlane (struct vec3 plane, struct vec3 normal, struct triangle in, struct triangle *out1, struct triangle *out2)
	Clip a triangle against a plane. More...
struct mesh *	MeshInit (int numTris)
	Initialize a new mesh object. More...
struct mesh *	MeshInitFromObj (char *objFile)
	Initialize a new mesh object from an obj file. More...
void	MeshDeinit (struct mesh *mesh)
	De-initializes the mesh object. More...
struct vec3	Mat4x4MultiplyVec3 (struct mat4x4 mat, struct vec3 vec)
struct mat4x4	Mat4x4Identity ()
struct mat4x4	Mat4x4RotateX (float rad)
struct mat4x4	Mat4x4RotateY (float rad)
struct mat4x4	Mat4x4RotateZ (float rad)
struct mat4x4	Mat4x4Translate (float x, float y, float z)
struct mat4x4	Mat4x4Project (float fovDegrees, float aspect, float near, float far)
struct mat4x4	Mat4x4Multiply (struct mat4x4 left, struct mat4x4 right)
struct mat4x4	Mat4x4InvertFast (struct mat4x4 matrix)
	Fast matrix inverse. Doesn't work if matrix does scaling.
struct mat4x4	Mat4x4PointAt (struct vec3 pos, struct vec3 target, struct vec3 up)
void	Mat4x4Debug (struct mat4x4 mat, char *name)
	Prints debug information about the 4x4 matrix.

Function Documentation

MeshDeinit()

void MeshDeinit

(

struct mesh *

mesh

)

De-initializes the mesh object.

Frees any memory allocated by the object and frees the pointer to the object itself.

Parameters

[in,out]

mesh

The mesh to be de-initialized

MeshInit()

struct mesh* MeshInit

(

int

numTris

)

Initialize a new mesh object.

This function is useful if a mesh needs to be explicitly, manually defined. Initialization here only refers to setting a valid "zero" state.

Parameters

[in]

numTris

the number of triangular faces the mesh will hold.

Returns

a properly "zeroed" mesh object that can support numTris faces.

MeshInitFromObj()

struct mesh* MeshInitFromObj

(

char *

objFile

)

Initialize a new mesh object from an obj file.

Loads the specified obj file and constructs a new mesh object representation of it.

Note: This doesn't read material definitions properly, instead explicitly loading a predefined texture out-of-band and applying it if there are texture coordinates in the obj file.

Parameters

[in]

objFile

path to the obj file to read

Returns

a mesh object representing the data in the obj file

See also

Features

TriangleClipAgainstPlane()

int TriangleClipAgainstPlane	(	struct vec3	plane,
		struct vec3	normal,
		struct triangle	in,
		struct triangle *	out1,
		struct triangle *	out2
	)

Clip a triangle against a plane.

Given a triangle and a plane, if some of the points lie on one side of the plane and some on the other, then split the triangle into 1 or 2 smaller triangles that do not pass through the plane.

Parameters

[in]	plane	point on the plane to clip against
[in]	normal	normal of the plane to clip against
[in]	in	the triangle to clip
[out]	out1	one of the smaller triangles resulting from the clipping, if necessary
[out]	out2	one of the smaller triangles resulting from the clipping, if necessary

Returns

0 if all points are outside the plane, 1 if the triangle is not clipped, otherwise the number of smaller triangles resulting from clipping.

Vec3IntersectPlane()

struct vec3 Vec3IntersectPlane	(	struct vec3	plane,
		struct vec3	normal,
		struct vec3	lineStart,
		struct vec3	lineEnd,
		float *	t
	)

Return the 3d point where a line intersects a plane.

Parameters

[in]	plane	3d point on the plane to intersect against
[in]	normal	normal of the plane to intersect against
[in]	lineStart
[in]	lineEnd
[out]	t	where on the line the intersection occurs.