goonscape/game/camera.go

package game

import (
	"math"

	rl "github.com/gen2brain/raylib-go/raylib"
)

var (
	cameraDistance = float32(20.0)
	cameraYaw      = float32(145.0)
	cameraPitch    = float32(45.0)
)

func UpdateCamera(camera *rl.Camera3D, player rl.Vector3, deltaTime float32) {
	wheelMove := rl.GetMouseWheelMove()
	if wheelMove != 0 {
		cameraDistance += -wheelMove * 5
		if cameraDistance < 10 {
			cameraDistance = 10
		}
		if cameraDistance > 250 {
			cameraDistance = 250
		}
	}

	if rl.IsKeyDown(rl.KeyRight) {
		cameraYaw += 100 * deltaTime
	}
	if rl.IsKeyDown(rl.KeyLeft) {
		cameraYaw -= 100 * deltaTime
	}
	if rl.IsKeyDown(rl.KeyUp) {
		cameraPitch -= 50 * deltaTime
		if cameraPitch < 20 {
			cameraPitch = 20
		}
	}
	if rl.IsKeyDown(rl.KeyDown) {
		cameraPitch += 50 * deltaTime
		if cameraPitch > 85 {
			cameraPitch = 85
		}
	}

	cameraYawRad := float64(cameraYaw) * rl.Deg2rad
	cameraPitchRad := float64(cameraPitch) * rl.Deg2rad

	camera.Position = rl.Vector3{
		X: player.X + cameraDistance*float32(math.Cos(cameraYawRad))*float32(math.Cos(cameraPitchRad)),
		Y: player.Y + cameraDistance*float32(math.Sin(cameraPitchRad)),
		Z: player.Z + cameraDistance*float32(math.Sin(cameraYawRad))*float32(math.Cos(cameraPitchRad)),
	}
	camera.Target = player
}