You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.go
    path of file: ./repos/raylib-go/examples/models/billboard
    
    the code of the file until where you have to start completion: package main

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

func main() {
	screenWidth := int32(800)
	screenHeight := int32(450)

	rl.InitWindow(screenWidth, screenHeight, "raylib [models] example - drawing billboards")

	camera := rl.Camera{}
	camera.Position = rl.NewVector3(5.0, 4.0, 5.0)
	camera.Target = rl.NewVector3(0.0, 2.0, 0.0)
	camera.Up = rl.NewVector3(0.0, 1.0, 0.0)
	camera.Fovy = 45.0
	camera.Projection = rl.CameraPerspective

	bill := rl.LoadTexture("billboard.png")      // Our texture billboard
	billPosition := rl.NewVector3(0.0, 2.0, 0.0) // Position where draw billboard

	rl.SetTargetFPS(60)

	for !rl.WindowShouldClose() {
		rl.UpdateCamera(&camera, rl.CameraOrbital) // Update camera with orbital camera mode

		rl.BeginDrawing()

		rl.ClearBackground(rl.RayWhite)

		rl.BeginMode3D(camera)

		rl.DrawGrid(10, 1.0) // Draw a grid

		rl.DrawBi
    
func main() {
	screenWidth := int32(800)
	screenHeight := int32(450)

	rl.InitWindow(screenWidth, screenHeight, "raylib [models] example - drawing billboards")

	camera := rl.Camera{}
	camera.Position = rl.NewVector3(5.0, 4.0, 5.0)
	camera.Target = rl.NewVector3(0.0, 2.0, 0.0)
	camera.Up = rl.NewVector3(0.0, 1.0, 0.0)
	camera.Fovy = 45.0
	camera.Projection = rl.CameraPerspective

	bill := rl.LoadTexture("billboard.png")      // Our texture billboard
	billPosition := rl.NewVector3(0.0, 2.0, 0.0) // Position where draw billboard

	rl.SetTargetFPS(60)

	for !rl.WindowShouldClose() {
		rl.UpdateCamera(&camera, rl.CameraOrbital) // Update camera with orbital camera mode

		rl.BeginDrawing()

		rl.ClearBackground(rl.RayWhite)

		rl.BeginMode3D(camera)

		rl.DrawGrid(10, 1.0) // Draw a grid

		rl.DrawBillboard(camera, bill, billPosition, 2.0, rl.White)

		rl.EndMode3D()

		rl.EndDrawing()
	}

	rl.UnloadTexture(bill) // Unload texture

	rl.CloseWindow()
}