bullet-hell/main.go

295 lines
6.7 KiB
Go

package main
import (
"fmt"
"math"
rl "github.com/gen2brain/raylib-go/raylib"
)
type movementPattern int
type shootingPattern int
const (
horizontal movementPattern = iota
circular movementPattern = iota
)
type game struct {
screenWidth int32
screenHeight int32
time int
enemies []*enemy
bullets []*bullet
}
type bullet struct {
pos rl.Vector2
speed rl.Vector2
size float32
dmg int
enemy bool
}
type player struct {
pos rl.Vector2
moveSpeed float32
bulletMoveSpeed float32
hitBoxRadius float32
}
type enemy struct {
pos rl.Vector2
health int
movePattern func(*enemy)rl.Vector2
shootPattern func()
hitBoxRadius float32
}
func (g game) insideArena(v rl.Vector2) bool {
return v.X >= 0 && v.Y >= 0 &&
v.Y <= float32(g.screenHeight) && v.X <= float32(g.screenWidth)
}
func (g *game) removeBullet(index int) {
g.bullets[index] = g.bullets[len(g.bullets)-1]
g.bullets = g.bullets[:len(g.bullets)-1]
}
func (b *bullet) update(g *game, index int) {
b.pos = rl.Vector2Add(b.pos, b.speed)
if !g.insideArena(b.pos) {
g.removeBullet(index)
return
}
rl.DrawCircleV(b.pos, b.size, rl.Yellow)
}
func (e *enemy) shoot(g *game) {
if g.time % 15 != 0 {
return
}
g.bullets = append(g.bullets, &bullet{
speed: rl.Vector2{X: 0, Y: 10},
size: 4,
dmg: 1,
enemy: true,
pos: e.pos,
})
}
func horizonalPattern(g *game) (func(*enemy)rl.Vector2) {
direction := rl.Vector2{X: 4, Y: 0}
return func(e *enemy) rl.Vector2 {
result := rl.Vector2Add(direction, e.pos)
if !g.insideArena(result) {
direction = rl.Vector2Negate(direction)
}
return result
}
}
func circlePattern(g *game, center rl.Vector2) (func(*enemy)rl.Vector2) {
t := float64(0.5)
return func(e *enemy) rl.Vector2 {
// x' = (x - x₀) * cos(θ) - (y - y₀) * sin(θ) + x₀
// y' = (x - x₀) * sin(θ) + (y - y₀) * cos(θ) + y₀
// x' = x * cos(θ) - y * sin(θ)
// y' = x * sin(θ) + y * cos(θ)
// result := center
//
// result.X = result.X + (e.pos.X - result.X) * float32(math.Cos(t)) -
// (e.pos.Y - result.Y) * float32(math.Sin(t))
//
// result.Y = result.Y + (e.pos.Y - result.Y) * float32(math.Sin(t)) +
// (e.pos.Y - result.Y) * float32(math.Cos(t))
result := center
result.X = result.X * float32(math.Cos(t)) - result.Y * float32(math.Sin(t))
result.Y = result.X * float32(math.Sin(t)) - result.Y * float32(math.Cos(t))
t += .08
return result
}
}
func (e *enemy) checkHit(g *game) (bool, *bullet, int) {
for index, bullet := range g.bullets {
playerBullet := !bullet.enemy
if !playerBullet {
continue
}
distance := rl.Vector2Distance(e.pos, bullet.pos) - bullet.size
// fmt.Println(distance)
if distance < e.hitBoxRadius {
return true, bullet, index
}
}
return false, nil, 0
}
func (g *game) killEnemy(index int) {
g.enemies[index] = g.enemies[len(g.enemies)-1]
g.enemies = g.enemies[:len(g.enemies)-1]
}
func (e *enemy) update(g *game, index int) {
if e.movePattern != nil {
e.pos = e.movePattern(e)
}
if hit, bullet, idx := e.checkHit(g); hit {
e.health -= bullet.dmg
g.removeBullet(idx)
}
if e.health <= 0 {
g.killEnemy(index)
return
}
e.shoot(g)
rl.DrawCircleV(e.pos, 5, rl.Blue)
}
func (p *player) move() {
if rl.IsKeyDown(rl.KeyW) { p.pos.Y -= p.moveSpeed }
if rl.IsKeyDown(rl.KeyS) { p.pos.Y += p.moveSpeed }
if rl.IsKeyDown(rl.KeyA) { p.pos.X -= p.moveSpeed }
if rl.IsKeyDown(rl.KeyD) { p.pos.X += p.moveSpeed }
}
func (p *player) shoot(g *game){
if g.time % 10 != 0 {
return
}
if rl.IsMouseButtonDown(rl.MouseLeftButton) {
// não leva em consideração a velocidade do jogador
mouse := rl.GetMousePosition()
direction := rl.Vector2Subtract(mouse, p.pos)
direction = rl.Vector2Normalize(direction)
g.bullets = append(g.bullets, &bullet{
pos: p.pos,
size: 2,
speed: rl.Vector2Scale(direction, p.bulletMoveSpeed),
dmg: 1,
enemy: false,
})
}
}
func (p *player) checkHit(g *game) {
for _, bullet := range g.bullets {
if !bullet.enemy {
continue
}
distance := rl.Vector2Distance(p.pos, bullet.pos) - bullet.size
// fmt.Println(distance)
if distance < p.hitBoxRadius {
fmt.Println("hit!")
}
}
}
func (p *player) update(g *game) {
p.move()
p.shoot(g)
p.checkHit(g)
// hitbox
rl.DrawCircleV(p.pos, p.hitBoxRadius, rl.Red)
// mira
mouse := rl.GetMousePosition()
inverted := rl.Vector2Subtract(p.pos, mouse)
inverted = rl.Vector2Negate(inverted)
inverted = rl.Vector2Normalize(inverted)
inverted = rl.Vector2Scale(inverted, 2000)
rl.DrawLineV(p.pos, rl.Vector2Add(mouse, inverted), rl.NewColor(255, 0, 0, 100))
}
func main() {
state := &game{screenWidth: 450, screenHeight: 700}
player := player{
pos: rl.Vector2{X: 100, Y: 100},
moveSpeed: 4,
bulletMoveSpeed: 8,
hitBoxRadius: 5,
}
rl.SetTraceLog(rl.LogWarning | rl.LogDebug)
rl.InitWindow(state.screenWidth, state.screenHeight, "danmaku")
rl.SetTargetFPS(60)
state.enemies = []*enemy{
{
pos: rl.Vector2{X: 200, Y: 200},
health: 1,
hitBoxRadius: 5,
movePattern: horizonalPattern(state),
},
{
pos: rl.Vector2{X: 169, Y: 222},
health: 1,
hitBoxRadius:5,
movePattern: horizonalPattern(state),
},
{
pos: rl.Vector2{X: 400, Y: 400},
health: 1,
hitBoxRadius:5,
// movePattern: circlePattern(state, rl.Vector2{X: 200, Y: 200}),
},
{
pos: rl.Vector2{X: 200, Y: 200},
health: 1,
hitBoxRadius:5,
// movePattern: circlePattern(state, rl.Vector2{X: 200, Y: 200}),
}}
for ; !rl.WindowShouldClose(); state.time += 1 {
rl.BeginDrawing()
rl.ClearBackground(rl.Black)
rl.DrawText("danmaku", 20, 20, 20, rl.DarkGray)
rl.DrawLine(18, 42, state.screenWidth-18, 42, rl.Black)
rl.DrawFPS(0, 0)
player.update(state)
for i := range state.enemies {
state.enemies[i].update(state, i)
}
for i := 0; i < len(state.bullets); i++ {
state.bullets[i].update(state, i)
}
rl.EndDrawing()
}
rl.CloseWindow()
}