engine.game Functions
This class contains functions to control the game logic of the application. It provides functionality for:
- Assigning a player to the Engine Camera viewport.
- Pausing, speeding up and slowing down rendering, physics or game logic.
Usage Example#
The example below creates a PlayerSpectator and sets it as the active Engine Camera. The player is rotated around Y axis with the specified speed, which is set via setScale():
- Pressing f slows down the game logic, so player's rotation slows down too.
- Pressing g speeds up the game logic and, therefore, player's rotation.
#include <core/unigine.h>
// declare a PlayerSpectator
PlayerSpectator player;
int init() {
// create a new PlayerSpectator instance
player = new PlayerSpectator();
// set necessary parameters: FOV, ZNear, ZFar, view direction vector and position.
player.setFov(90.0f);
player.setZNear(0.1f);
player.setZFar(10000.0f);
player.setViewDirection(vec3(0.0f, 1.0f, 0.0f));
player.setWorldPosition(dvec3(-1.6f, -1.7f, 1.7f));
// set the player to the Game singleton instance
engine.game.setPlayer(player);
return 1;
}
int update() {
// slow down the game logic
if (engine.app.clearKeyState('f')) {
engine.game.setScale(0.2f);
log.message("Game logic speed has been decreased. Frame duration is %f seconds\n", engine.game.getFTime());
}
// speed up the game logic
if (engine.app.clearKeyState('g')) {
engine.game.setScale(2.0f);
log.message("Game logic speed has been increased. Frame duration is %f seconds\n", engine.game.getFTime());
}
// rotate the player 45 degrees per second around Y axis
player.setWorldRotation(player.getWorldRotation() * quat(0.0f, 1.0f, 0.0f, 45.0f * engine.game.getIFps()));
return 1;
}
See Also#
- The article on the GameIntersection class as a usage example of game intersections
- A set of UnigineScript API samples located in the <UnigineSDK>/data/samples/systems/ folder:
- noise_00
- random_00
Game Class
Members
void engine.game.setData ( string data ) #
Sets user data associated with the game logic. This string is written directly into a *.world file. Namely, into the data child tag of the game tag, for example:<world version="1.21">
<game>
<data>User data</data>
</game>
</world>
Arguments
- string data - User data. Data can contain an XML formatted string.
string engine.game.getData ( ) #
Returns user data associated with the game logic. This string is written directly into a *.world file. Namely, into the data child tag of the game tag, for example:<world version="1.21">
<game>
<data>User data</data>
</game>
</world>
Return value
User data. Data can contain an XML formatted string.void engine.game.setEnabled ( int enabled ) #
Pauses or resumes the game logic.Arguments
- int enabled - 1 to resume the game logic, 0 to pause it.
int engine.game.isEnabled ( ) #
Returns a value indicating if the game is paused or not.Return value
1 if the game logic is not paused; otherwise, 0.void engine.game.setFrame ( int frame ) #
Sets the game frame with the given number as the current one.Arguments
- int frame - Frame number.
int engine.game.getFrame ( ) #
Returns the number of the current game frame.// get the current game frame
int loading_frames = engine.game.getFrame();
// perform asynchronous nodes loading
// ...
// calculate the number of game frames required for nodes loading
loading_frames = engine.game.getFrame() - loading_frames;
Return value
Frame number.void engine.game.setIFps ( float ifps ) #
Sets the scaled inverse FPS value (the time in seconds it took to complete the last frame). This function sets a fixed FPS that does not depend on the real FPS the hardware is capable of. That is, it forces constant frame time increments between rendered frames, used for animation/expression update etc. To remove the FPS limitation, use -1.The function is useful when grabbing the video reel with a fixed FPS value (for example, 25 frames per second).
Arguments
- float ifps - Inverse FPS value (1/FPS) in seconds.-1 removes the FPS limitation.
float engine.game.getIFps ( ) #
Returns the scaled inverse FPS value (the time in seconds it took to complete the last frame). This value does not depend on the real FPS the hardware is capable of. -1 means no Inverse FPS value is set.Node node;
// ...
// get an inverse FPS value
float ifps = engine.game.getIFps();
// move the node up by 0.1 unit every second instead of every frame
node.worldTranslate(Vec3(0.0f, 0.0f, 0.1f*ifps));
Return value
Scaled inverse FPS value (1/FPS) in seconds. If the game is paused, 0 is returned.Obstacle engine.game.getIntersection ( Vec3 p0, Vec3 p1, float radius, int mask, int[] exclude, GameIntersection intersection ) #
Performs intersection to find if a pathfinding Obstacle is located within the cylinder between two points. The specified obstacles will be ignored.
Arguments
- Vec3 p0 - Start point.
- Vec3 p1 - End point.
- float radius - Radius of the intersection cylinder.
- int mask - Obstacle intersection mask. The obstacle is ignored if its mask does not match.
- int[] exclude - Array with excluded obstacles. These obstacle nodes are ignored when performing intersection.
- GameIntersection intersection - GameIntersection class instance to put the result into.
Return value
Intersected obstacle.Obstacle engine.game.getIntersection ( Vec3 p0, Vec3 p1, float radius, int mask, GameIntersection intersection ) #
Performs intersection to find if a pathfinding obstacle is located within the cylinder between two points.
The following example shows how you can get the intersection point (vec3) of the cylinder between two points with an obstacle. In this example the cylinder is an invisible traced cylinder from the point of the camera (vec3 p0) to the point of the mouse pointer (vec3 p1) with the specific radius. The executing sequence is the following:
- Define and initialize two points (p0 and p1) by using the getPlayerMouseDirection() function from core/scripts/utils.h.
- Create an instance of the GameIntersection class to get the intersection point coordinates.
- Check, if there is a intersection with an obstacle. The engine.game.getIntersection() function returns an intersected obstacle when the obstacle appears in the area of the cylinder.
- After that GameIntersection instance gets the point of the nearest intersection point and you can get it by using the getPoint() function.
#include <core/scripts/utils.h>
/* ... */
// define two vec3 coordinates
vec3 p0,p1;
// get the mouse direction from camera (p0) to cursor pointer (p1)
getPlayerMouseDirection(p0,p1);
// create an instance of the GameIntersection class
GameIntersection intersection = new GameIntersection();
// try to get the intersection with an obstacle.
// cylinder has radius 0.1f, intersection mask equals to 1
Obstacle obstacle = engine.game.getIntersection(p0,p1,0.1f, 1, intersection);
// check, if the intersection of mouse direction with any obstacle was occurred;
if(obstacle !=NULL)
{
// show the coordinates of the intersection in console
log.message("The intersection with obstacle was here: %s\n", typeinfo(intersection.getPoint()));
}
/* ... */
Arguments
- Vec3 p0 - Start point.
- Vec3 p1 - End point.
- float radius - Radius of the intersection cylinder.
- int mask - Obstacle intersection mask. The obstacle is ignored if its mask does not match.
- GameIntersection intersection - GameIntersection class instance to put the result into.
Return value
Intersected obstacle.Variable engine.game.getNoise ( Variable pos, Variable size, int frequency ) #
Returns a noise value calculated using a Perlin noise function. Variable can be of the int or vec3 type.Image image;
int size = 64;
float time = engine.game.getTime();
vec3 position;
position.z = time;
forloop(int y = 0; size) {
position.y = y * 0.05f;
forloop(int x = 0; size) {
position.x = x * 0.05f;
// generate Perlin noise for the image pixels
float n = engine.game.getNoise(position,vec3(32.0f,32.0f,32.0f),6);
image.set2D(x,y,n,-n,n * n);
}
}
Arguments
Return value
Noise value.float engine.game.getNoise1 ( float pos, float size, int frequency ) #
Returns a noise value calculated using a Perlin noise function.Arguments
- float pos - Float position.
- float size - Size of the noise.
- int frequency - Noise frequency.
Return value
Noise value.float engine.game.getNoise2 ( vec2 pos, vec2 size, int frequency ) #
Returns a 2D noise value calculated using a Perlin noise function.Arguments
Return value
2D noise value.float engine.game.getNoise3 ( vec3 pos, vec3 size, int frequency ) #
Returns a 3D noise value calculated using a Perlin noise function.Arguments
Return value
3D noise value.void engine.game.setPlayer ( Player player ) #
Assigns a new player to the Engine Camera viewport.// create a new player
PlayerDummy dummy = new PlayerDummy();
// set necessary parameters
dummy.setPosition(Vec3(-20.0f,0.0f,15.0f));
dummy.setDirection(vec3(1.0f,0.0f,-0.8f));
// set the player to the Engine Camera viewport
engine.game.setPlayer(dummy);
Arguments
- Player player - Player to set as a current one.
Player engine.game.getPlayer ( ) #
Returns the current player assigned to the Engine Camera viewport.// get the current player (engine camera)
Player player = engine.game.getPlayer();
// correct player position
player.setPosition(Vec3(-92.0f,94.0f,190.0f));
// set the updated player to the Engine Camera viewport
engine.game.setPlayer(player);
Return value
Current player.unsigned int engine.game.getRandom ( ) #
Returns a pseudo-random integer number.Return value
Random integer number.Variable engine.game.getRandom ( Variable from, Variable to ) #
Returns a pseudo-random number of the given type (end-point not included). Variable can be of one of the following types: int, float, vec3, vec4, dvec3, dvec4, ivec3, ivec4.// create a WidgetLabel
label = new WidgetLabel(gui,"Text sample");
// specify widget settings
label.setFontOutline(1);
label.setFontSize(9);
// get pseudo-random values
int x = engine.game.getRandom(0,engine.app.getWidth() - 128);
int y = engine.game.getRandom(0,engine.app.getHeight() - 128);
// use the generated values to set widget position
label.setPosition(x,y);
Arguments
Return value
Random number.double engine.game.getRandomDouble ( double from, double to ) #
Returns a pseudo-random double number within a given range (end-point not included).Arguments
- double from - The initial point of the range.
- double to - The end point of the range.
Return value
Random double integer number.float engine.game.getRandomFloat ( float from, float to ) #
Returns a pseudo-random float number within a given range (end-point not included).Arguments
- float from - The initial point of the range.
- float to - The end point of the range.
Return value
Random float number.int engine.game.getRandomInt ( int from, int to ) #
Returns a pseudo-random integer number within a given range (end-point not included).Arguments
- int from - The initial point of the range.
- int to - The end point of the range.
Return value
Random integer number.void engine.game.setScale ( float scale ) #
Sets a value that is used to scale frame duration. It scales up or down the speed of rendering, physics and game logic. This function can be used to create effects of slow/accelerated motion.
For example, if the scale equals 2, the rate of simulation of all effects (such as particles) speeds up to two times faster. As for physics, in reality it will be simulated with the same fixed physics FPS, but the number of iterations will be two times higher. It is possible to scale the physics FPS separately via engine.physics.setScale() function.
This function scales the value set by the setIFps().
Arguments
- float scale - Scaling factor. The provided values is clamped within the range [0;32].
float engine.game.getScale ( ) #
Returns a value used to scale the frame duration.Return value
Value to scale the frame duration.void engine.game.setSeed ( int seed ) #
Sets the seed for pseudo-random number generator.Arguments
- int seed - Number used to initialize a pseudo-random sequence of numbers.
int engine.game.getSeed ( ) #
Returns the seed for pseudo-random number generator.Return value
Number used to initialize a pseudo-random sequence of numbers.void engine.game.setTime ( float time ) #
Sets the time value for the game. The time is counted off starting from the world loading and does not take game pauses into account.Arguments
- float time - Time in seconds.
float engine.game.getTime ( ) #
Returns the current time spent in the game. It is counted off starting from the world loading and does not take game pauses into account.Return value
Time in seconds.vec4 engine.game.getRandomColor ( ) #
Returns a random generated color vector: (R, G, B, A).Return value
Four-component vec4 vector representing a color: (R, G, B, A).void engine.game.setPlayerListener ( Player listener ) #
Sets the player as listener.Arguments
- Player listener - Player to be set as listener.