Questions tagged [trigonometry]
A branch of mathematics that studies triangles and the relationships between their sides and the angles between these sides.
117
questions
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1answer
29 views
Pygame : problem with calculating an angle between two points
I've been struggling to calculate the angle alpha between an object and a certain point M so that I can move that object to M.
To calculate alpha, I'm using ...
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0answers
56 views
How to decay sine or cosine wave so it takes one additional period to reach equilibrium
In many shmups, when enemies arrive, they accelerate onto screen, decelerate, and overshoot their static arrival position slightly, before backing up slowly to the position. This can be seen in many ...
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1answer
22 views
How to find if a Ray intersects a Triangle Clockwise or Counter Clockwise
I have a Triangle with an intersecting Ray.
How can I find out if the triangle's vertices are in a clockwise or counter clockwise rotation order with respect to the Ray?
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0answers
39 views
How to unfold a spiral of balls?
I have a spiral made of balls. It's a spiral with equally distributed balls using the following formula (see link on math.stackexchange).
This is how it looks like:
Now, the spiral is rolling ...
2
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1answer
35 views
How to add zombie arms to enemies in HTML canvas
I'm making a game with HTML canvas (not WEBGL). I have zombies that go to the center of the screen, but for now they are just circles. I want to give them two arms, like the arms players have in ...
2
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1answer
164 views
Any fast alternative to sine in GLSL?
Should I just use the built-in sin() function or my custom sine function?
I'm concerned about performance here. I don't care about accuracy much here because I use it to just get wave effects in my ...
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0answers
24 views
Get direction vector of camera in voxel game
I am currently working on a Minecraft clone (a voxel game). The feature I'm working on is the ability to break blocks. I have a ray-casting/ray tracing algorithm for traversing the voxels, but the ...
2
votes
1answer
44 views
Position Object always at the same distance of 2 other moving Objects?
I am making a procedural animation of a worm. I have already something working:
(the green dot is the position Target, purple and red are the Head and the Tail of the Worm)
I would like to add ...
0
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2answers
195 views
When are oblique triangles used in game development?
I'm working on a project that explains how trigonometry is used in video games, and I need to mention oblique triangles.
However, as far as I know, only right triangle diagrams are used in video games ...
4
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1answer
230 views
space map generation
I am at the beginning of the creation of a space 4x and first of all i need to generate a galaxy of stars linked by connecting lines that changes in each new game, I'll add a few pictures to show what ...
0
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1answer
73 views
Convert GPS coordinates into Unity world space?
I am developing an AR application where a number of historical buildings are spawned around the player depending on his position when a target / QR Code is recognized.
I know the Lat/Lon of these ...
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0answers
32 views
How To Place Object On Ground Within Radius?
I'm using Unity and I'm building an object placement system where you'll be able to position objects around the player.
I'd like to place objects flush with the ground, parallel to world up, even on ...
0
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1answer
36 views
3d points to rotation matrix of orientation
I have a vector in a 3D view, defined by a point p1(x1, y1, z1) and a rotation r1(x1, y1, z1). I can get a direction and a yaw. I need that vector to point another point p2 (x2, y2, z2). So I need a ...
0
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1answer
319 views
Arc length between two angles
As I calculate the length of the arc (green) between two angles;
I need a method like:
arc_lenght (xpos, ypos, radius, ang1, ang2) {
return arc_lenght
}
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0answers
105 views
Pong paddle and deflection angles
I'm trying to make a pong clone and am having trouble grasping ball deflection. The way I'm approaching it is to increase the angle by how far the ball collides from the middle of the paddle. However, ...
1
vote
2answers
203 views
Why are rotations in 2D game engines often counter-clockwise = positive systems?
I was looking over the API for a game engine a friend was developing in her spare time. She made the decision to make positive angles rotate in a clockwise direction. This immediately struck me as odd....
1
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1answer
247 views
SIMD and Inverse Tangent
I'm calculating spherical UV coordinates in a loop, trying to get GCC to vectorize the code.
Here's a compile-able example of what it looks like.
...
2
votes
1answer
74 views
Triangular Metric
Given a point inside a unit equilateral triangle, how does one rotate it across the triangle perimeter? I.e. the triangle outline serving the same purpose as circle's circumference. That is actually a ...
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2answers
81 views
I need help with calculating the angle my character is aiming at
So im doing this program where i want my hero to shoot to the direction its facing , but for this job to get done i need to calculate the angle my hero is facing with Math.atan2() , atleasts thats ...
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0answers
43 views
Adding spread to velocity Vector3D
I am trying to give an object a velocity spread (e.g. shotgun bullets or particle effect).
...
1
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2answers
105 views
How to get the Javascript equivalent of GameMaker's `hspeed` and `vspeed` given only `direction` and `speed`?
I'm using a NodeJS server to control NPC movement in a multiplayer game, and when they get too close to the edge of the room I need to reverse either the horizontal or vertical components of their ...
1
vote
1answer
51 views
Sum of FoV enemies
so what I need is to calculate the sum of players' Field of view.
Put simple, In a 2d space, I want to check how much they cover (in degrees).
So here are a couple of use cases to explain by example:
...
0
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0answers
36 views
Camera LookAt position with fixed screen position
I have a perspective "lookAt-type" camera. I'm trying to compute specific focus point of the camera, which should be placed in the middle of the screen: I also have a custom 3d point in world space, ...
0
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1answer
58 views
Finding Closest of 8 Possible Angles to Theta Value
I'm working on creating a gesture recognition system, and I saw one simple implementation that isn't as accurate, but is really easy to implement. The idea is that you have a unit circle with the 8 ...
0
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2answers
119 views
How to panning camera on XZ axis with different angles
I have an Orthographic camera where the position is { x:0, y:100, z:0 } and is pointing/looking at { x:0, y:0, z:0 }. At this ...
2
votes
1answer
29 views
Why does the first red-zone sometimes appear too close to the border in my battle-royale red-zone feature?
The Problem:
If you've ever played or watched some gameplay of a battle royal game (like PUBG, for example), you'll always find an event during any battle called the red zone.
Basically, at a ...
0
votes
1answer
148 views
Combine rotation XZ (horizontal) with YZ (vertical). Math formula
I'm trying to make a rotation vertically and horizontally around a point at the same time but I'm not able to combine both.
I have this formula for the horizontal rotation:
...
1
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2answers
210 views
Algorithm to produce a 2D 'flying through space' effect like the old Windows screen saver
I am old. My high school maths is a long way in my past and I am struggling to devise an algorithm that will produce a 2D 'flying through space' effect like the old Windows screen saver. It has—
...
0
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1answer
31 views
Getting an object to move in another objects direction
I have a player and an enemy, both have x and y values, and I want to move the enemy to the player and have them 'touch' over time in a speed that I can determine, I tried calculating the angle ...
1
vote
1answer
579 views
Move object at angle like a sine wave
I currently have this code, which moves an object in a straight line at an angle, where "dir" is the angle.
velX = (float)(Math.cos(Math.toRadians(dir))) * speed;
...
1
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1answer
48 views
Aim/Scope Oscillation Algorithm
I have been struggling to find an algorithm to implement something that will make a direction oscillate within a cone constraint, in a helix-shaped fashion as in photo (it will always go back to the ...
2
votes
3answers
242 views
Are there recursive variants for trigonometric functions to potentially improve performance?
This is perhaps a better question for mathematics SE, however, this deals more with the performance side of gaming, and software in general. When I say recursive function, I mean recurrence relation.
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2answers
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How can I correct an unwanted fisheye effect when drawing a scene with raycasting?
Hello I have a game using raycasting for the TI Nspire in Lua, and when the player faces a wall so that their degree they are facing is perpendicular to the length of the wall, I am having what is ...
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0answers
122 views
Calculate smooth transition between local space angles
I'm trying to calculate direction of moving character (to rotate it's animation).
I have something like this:
Character can have 4 cardinal directions. The rotation is calculated from the current ...
0
votes
1answer
44 views
Moving a point on a rotating sprite
I've been trying to get sprites to stay on a set point on another rotating sprite. At the moment, it's very inaccurate, the original position is wrong, and when the rotation is applied the sprite ...
0
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0answers
17 views
How to calculate Camera “correct” position and distance to Frame all my Scene? [duplicate]
Consider I have N dynamic points on my Scene, I would like to "frame" all them, with my Camera.
How can i calculate (at runtime) Vector3 Position to correctly frame all my scene ?
This is my idea:
...
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0answers
540 views
Help with simple 2D Lens Flare effect
I'm currently trying to do a Lens Flare effect in a 2D game (Unity 3D) and i'm having problems with element positioning.
This are my elements in hierarchy. "Camera Container" it's a GameObject, ...
3
votes
2answers
789 views
1
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1answer
89 views
Why is my sprite moving 90 degrees to the right?
I have a sprite which i'm trying to move towards the top of the screen with the left and right buttons adjusting the heading.
However when my heading = 0; my ...
0
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1answer
587 views
Getting the current 'Forward' direction Vector values into code and how to use them?
Im having some trouble visualising how the maths works for this particular problem. Back when i coded in 2d only this was often a stumbling point for mine even when only dealing with an x and y axis.
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2answers
554 views
Why doesn't games use CORDIC for sin and cos?
If the game devs add CORDIC sin cos calculation to their games, their games will have much better FPS. Why do they use normal sin cos function (e.g. Math.sin) instead of CORDIC?
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1answer
659 views
Unity Mathf.Atan2 algorithm complexity
using Unity5.5.1f;
using C#;
So I have a circle (2D) divided equally by 16 directions, and I also have a direction V which is different from the other 16.
In order to know which direction is the ...
2
votes
1answer
162 views
Translating yaw degrees into 2D movement
I've been hitting my head on the wall for a while with this, and I'm almost sure I'm overcomplicating it.
I have a variable for yaw in degrees (and also pitch and roll, but those should be irrelevant)...
3
votes
1answer
157 views
Math behind drawing one game object relative to another?
Let's say I have a square (a) and I want to draw another square (b) that stays on one corner of the square (a).
Square (a) can rotate and move around the game world, what math would be used to keep ...
1
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2answers
163 views
Dealing with vectors in multiple planes
Say I have my main "screen" plane, where vectors can be represented
I "know"/can represent vector Q, but the only information I know about vector R is relative to Vector Q. An easy way to visualize ...
1
vote
2answers
1k views
Find vector tangent to circle through a point
C2 and P1 are known points. Radius of circle C2 is also constant and known. I am trying to find point T to eventually construct line p1-t, which is tangent to circle c2.
I have made an attempt ...
0
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1answer
763 views
Mapping polar coordinates to cube
I am trying map polar coordinates to points on a cube. I was able to map the front, back, left and right faces of the cube, but I am struggling with the top and bottom. Here is what I have:
...
0
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2answers
2k views
LibGDX How can I draw a line at a specific angle
I'm working on a 2D platformer, shooter game and I'm attempting to draw a line to serve as a guide to indicate where the player is shooting. The line should be drawn from the player's sprite to the ...
0
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1answer
51 views
Coordinates of the corners of a rectangle bridging two circles
I am implementing a game that involves slingshots and circular objects. I have gotten the basic "geometric" construction down for rendering the slingshot, but I am having trouble implementing this in ...
0
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2answers
54 views
How to work out the height of a point on a tilted surface?
I have a plane which gets tilted on the X and Z axis (y+ is the normal).
Given an X and Z coordinate and the X and Z rotation of the plane, how do I find out the height (Y) at that point?
I assume ...
