engine.h File Reference

Global physics engine declarations. More...

#include "cmdfx/core/sprites.h"

Go to the source code of this file.

Functions
int	Sprite_isStatic (CmdFX_Sprite *sprite)
	Gets whether this sprite is static.
int	Sprite_setStatic (CmdFX_Sprite *sprite, int isStatic)
	Sets whether this sprite is static.
double	Engine_getForceOfGravity ()
	Gets the force of gravity, in characters per second squared.
int	Engine_setForceOfGravity (double force)
	Sets the force of gravity, in characters per second squared.
double	Engine_getTerminalVelocity ()
	Gets the terminal velocity, in characters per second.
int	Engine_setTerminalVelocity (double velocity)
	Sets the terminal velocity, in characters per second.
int	Engine_getGroundY ()
	Gets the Y level of the ground for the physics engine.
int	Engine_setGroundY (int y)
	Sets the Y level of the ground for the physics engine.
double	Engine_getDefaultFrictionCoefficient ()
	Gets the default friction coefficient for a sprite.
int	Engine_setDefaultFrictionCoefficient (double coefficient)
	Sets the default friction coefficient for a sprite.
double	Engine_getCharacterMass (char c)
	Gets the default mass of a character.
int	Engine_setCharacterMass (char c, double mass)
	Sets the default mass of a character.
int	Engine_start ()
	Starts up the physics engine.
CmdFX_Sprite **	Engine_tick ()
	Ticks the physics engine.
int	Engine_cleanup ()
	Cleans up the physics engine.
int	Engine_end ()
	Stops the physics engine.

Detailed Description

Global physics engine declarations.

Author

Gregory Mitchell (me@gm.nosp@m.itch.nosp@m.215.x.nosp@m.yz)

Version

0.1.1

Date

2025-02-09

Copyright

Copyright (c) 2025

Function Documentation

Engine_cleanup()

int Engine_cleanup

(

)

Cleans up the physics engine.

This is different from Engine_end, in that it claens up any loose variables before stopping the engine. This is automatically called by Engine_end and is not intended to be called independently to avoid undefined behavior.

Returns

0 if successful, -1 if an error occured.

Engine_end()

int Engine_end

(

)

Stops the physics engine.

Returns

0 if successful, -1 if an error occured.

Engine_getCharacterMass()

double Engine_getCharacterMass

(

char

c

)

Gets the default mass of a character.

The mass of a sprite is calculated by the number of non-whitespace characters in a sprite map. ANSI codes have no effect on the mass of a character.

You can modify the output value of Sprite_getDefaultMass by changing the default mass of a character. Every character by default has a mass of 1.

Returns

The default mass of a character.

Engine_getDefaultFrictionCoefficient()

double Engine_getDefaultFrictionCoefficient

(

)

Gets the default friction coefficient for a sprite.

The default friction coefficient is a value between 0 and 1 that determines how much friction is applied to a sprite. A value of 0 means no friction, while a value of 1 means full friction, meaning it will stop immediately.

The default value is 0.25.

Returns

The default friction coefficient.

Engine_getForceOfGravity()

double Engine_getForceOfGravity

(

)

Gets the force of gravity, in characters per second squared.

This method returns the force of gravity, in characters per second squared. The default value is 1.0 c/s^2.

Returns

The force of gravity, in c/s^2.

Engine_getGroundY()

int Engine_getGroundY

(

)

Gets the Y level of the ground for the physics engine.

The default value is the canvas height, because (0, 0) refers to the top left of the terminal. The Y level of the ground helps determine when a sprite has landed on the ground.

Returns

The Y level of the ground.

Engine_getTerminalVelocity()

double Engine_getTerminalVelocity

(

)

Gets the terminal velocity, in characters per second.

This method returns the terminal velocity, in characters per second. The default value is 10.0 c/s.

Returns

The terminal velocity, in c/s.

Engine_setCharacterMass()

int Engine_setCharacterMass	(	char	c,
		double	mass )

Sets the default mass of a character.

The mass of a sprite is calculated by the number of non-whitespace characters in a sprite map. ANSI codes have no effect on the mass of a character.

You can modify the output value of Sprite_getDefaultMass by changing the default mass of a character. Every character by default has a mass of 1.

Parameters

c	The character to set the mass of.
mass	The default mass of the character.

Returns

0 if successful, -1 if an error occured.

Engine_setDefaultFrictionCoefficient()

int Engine_setDefaultFrictionCoefficient

(

double

coefficient

)

Sets the default friction coefficient for a sprite.

The default friction coefficient is a value between 0 and 1 that determines how much friction is applied to a sprite. A value of 0 means no friction, while a value of 1 means full friction, meaning it will stop immediately.

The default value is 0.25.

Parameters

coefficient

The default friction coefficient.

Returns

0 if successful, -1 if an error occured.

Engine_setForceOfGravity()

int Engine_setForceOfGravity

(

double

force

)

Sets the force of gravity, in characters per second squared.

This method sets the force of gravity, in characters per second squared. The default value is 1.0 c/s^2.

Parameters

force

The force of gravity, in c/s^2.

Returns

0 if successful, -1 if an error occurred.

Engine_setGroundY()

int Engine_setGroundY

(

int

y

)

Sets the Y level of the ground for the physics engine.

The default value is the canvas height. The Y level of the ground helps determine when a sprite has landed on the ground.

Parameters

y	The Y level of the ground.

Returns

0 if successful, -1 if an error occurred.

Engine_setTerminalVelocity()

int Engine_setTerminalVelocity

(

double

velocity

)

Sets the terminal velocity, in characters per second.

This method sets the terminal velocity, in characters per second. The default value is 10 c/s.

Parameters

velocity

Returns

0 if successful, -1 if an error occurred.

Engine_start()

int Engine_start

(

)

Starts up the physics engine.

This method starts up the physics engine. This method will automatically enable thread safety if it is not already enabled.

Returns

0 if successful, -1 if an error occured.

Engine_tick()

CmdFX_Sprite ** Engine_tick

(

)

Ticks the physics engine.

This method ticks the physcis engine, if it is running. This is automatically called once per frame.

Returns

An array of all sprites that were modified by the engine. The array is terminated with a NULL pointer. The array is automatically freed by the engine, so it should not be freed by the caller.

Sprite_isStatic()

int Sprite_isStatic

(

CmdFX_Sprite *

sprite

)

Gets whether this sprite is static.

A sprite is static if it is not affected by the physics engine.

Parameters

sprite

The sprite to check.

Returns

1 if the sprite is static, 0 otherwise.

Sprite_setStatic()

int Sprite_setStatic	(	CmdFX_Sprite *	sprite,
		int	isStatic )

Sets whether this sprite is static.

A sprite is static if it is not affected by the physics engine. Use this method to set whether a sprite is static or not.

Parameters

sprite	The sprite to modify.
isStatic	1 if the sprite is static, 0 otherwise.

Returns

0 if successful, -1 if an error occurred.