I am working on a game. This game is top down, real-time, and must feature pathing. My game must calculate the angle between a player's current position and the one they click to walk to.
Problem is, I am using screen coordinates, as in "x increases to the right, y increases to the bottom"
Here's where I'm at with some code
package main
import (
"fmt"
"math"
)
func main() {
position1 := &Position{550, 200}
position2 := &Position{700, 500}
vector1 := CreatePathVector(position1, position2, 50)
fmt.Printf("position1: %v
position2: %v
", position1, position2)
position := position1
for i := 0; i < 5; i++ {
position = position.Add(vector1)
fmt.Printf("next position: %v
", position)
}
position3 := &Position{400, 500}
position4 := &Position{700, 400}
vector2 := CreatePathVector(position3, position4, 50)
fmt.Printf("position3: %v
position4: %v
", position3, position4)
position = position3
for i := 0; i < 5; i++ {
position = position.Add(vector2)
fmt.Printf("next position: %v
", position)
}
}
type Position struct {
X float64
Y float64
}
type Vector struct {
Radians float64
Distance float64
}
func CreatePathVector(pos1 *Position, pos2 *Position, speed int) *Vector {
ydiff := pos2.Y - pos1.Y
xdiff := pos2.X - pos1.X
radians := math.Atan2(ydiff, xdiff)
return &Vector{
Radians: radians,
Distance: float64(speed),
}
}
func (p *Position) Add(v *Vector) *Position {
return &Position{
X: p.X + math.Sin(v.Radians)*v.Distance,
Y: p.Y + math.Cos(v.Radians)*v.Distance,
}
}
Here is the output
position1: &{550 200}
position2: &{700 500}
next position: &{594.7213595499958 222.3606797749979}
next position: &{639.4427190999916 244.72135954999578}
next position: &{684.1640786499873 267.0820393249937}
next position: &{728.8854381999831 289.44271909999156}
next position: &{773.6067977499789 311.80339887498945}
position3: &{400 500}
position4: &{700 400}
next position: &{384.1886116991581 547.4341649025257}
next position: &{368.37722339831623 594.8683298050514}
next position: &{352.56583509747435 642.3024947075771}
next position: &{336.75444679663246 689.7366596101028}
next position: &{320.9430584957906 737.1708245126285}
As you can see, in both examples, the steps of adding the vector repeatedly does not steer towards the destination