59 lines
1.8 KiB
Go
59 lines
1.8 KiB
Go
package main
|
|
|
|
import (
|
|
"math/rand"
|
|
"time"
|
|
|
|
rl "github.com/gen2brain/raylib-go/raylib"
|
|
)
|
|
|
|
type Particle struct {
|
|
Pos rl.Vector2
|
|
Vel rl.Vector2
|
|
Size float32
|
|
}
|
|
|
|
var particles []Particle
|
|
var topColor = rl.Color{R: 0x20, G: 0x0F, B: 0x3C, A: 0xFF} // #200F3C top
|
|
var bottomColor = rl.Color{R: 0x3B, G: 0x0B, B: 0x42, A: 0xFF} // #3B0B42 bottom
|
|
var particleColor = rl.Color{R: 0xD4, G: 0xB0, B: 0xB5, A: 0x80} // D4B0B5 with some transparency
|
|
|
|
var rng = rand.New(rand.NewSource(time.Now().UnixNano())) // Local RNG
|
|
|
|
func InitBackground(width, height int) {
|
|
particles = make([]Particle, 100)
|
|
for i := range particles {
|
|
particles[i].Pos = rl.Vector2{X: float32(rng.Intn(width)), Y: float32(rng.Intn(height))}
|
|
particles[i].Vel = rl.Vector2{X: (rng.Float32() - 0.5) * 0.2, Y: (rng.Float32() - 0.5) * 0.2}
|
|
particles[i].Size = rng.Float32()*1.5 + 0.5 // Particles size ~0.5-2.0
|
|
}
|
|
}
|
|
|
|
func UpdateBackground(screenWidth, screenHeight int) {
|
|
deltaTime := rl.GetFrameTime() // Time in seconds since the last frame
|
|
for i := range particles {
|
|
particles[i].Pos.X += particles[i].Vel.X * deltaTime * 60 // Adjust for frame rate
|
|
particles[i].Pos.Y += particles[i].Vel.Y * deltaTime * 60
|
|
|
|
// Wrap around screen
|
|
if particles[i].Pos.X < 0 {
|
|
particles[i].Pos.X += float32(screenWidth)
|
|
} else if particles[i].Pos.X > float32(screenWidth) {
|
|
particles[i].Pos.X -= float32(screenWidth)
|
|
}
|
|
if particles[i].Pos.Y < 0 {
|
|
particles[i].Pos.Y += float32(screenHeight)
|
|
} else if particles[i].Pos.Y > float32(screenHeight) {
|
|
particles[i].Pos.Y -= float32(screenHeight)
|
|
}
|
|
}
|
|
}
|
|
|
|
func DrawBackground(screenWidth, screenHeight int) {
|
|
// Draw vertical gradient
|
|
rl.DrawRectangleGradientV(0, 0, int32(screenWidth), int32(screenHeight), topColor, bottomColor)
|
|
// Draw particles
|
|
for _, p := range particles {
|
|
rl.DrawCircleV(p.Pos, p.Size, particleColor)
|
|
}
|
|
}
|