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package main
import (
"github.com/veandco/go-sdl2/sdl"
// "golang.org/x/exp/io/spi"
// "github.com/veandco/go-sdl2/sdl"
)
// Unicorn ...
// Object representing the Unicorn HAT to be controlled
type Unicorn interface {
// Not all unicorns are the same size
GetWidth() uint8
GetHeight() uint8
// Array of pixels, indexed x, then y, then color (rgb)
GetPixels() [][][]uint8
// Set an individual pixel
SetPixel(x, y, r, g, b uint8)
// Flip the display buffer
Show()
// Set all pixels back to black
Clear()
// Turns off the LEDs
Off()
}
// GetUnicorn ...
// Get a unicorn. Tries to get you a real one,
// if it can't find one then gives you a fake one.
func GetUnicorn() (unicorn Unicorn, err error) {
// unicorn, err = NewReal()
// if err != nil {
// log.Println("Couldn't get a real unicorn, trying a fake one")
// unicorn, err = NewFake(int8(16), int8(16))
// }
unicorn, err = NewFake(uint8(16), uint8(16))
return
}
// FakeUnicorn ...
// Shows an SDL window pretending to be a unicorn.
type FakeUnicorn struct {
pixels [][][]uint8
displayWidth int32
displayHeight int32
window *sdl.Window
renderer *sdl.Renderer
}
// NewFake ...
// Constructs a new fake unicorn out of paint and glue
func NewFake(width, height uint8) (*FakeUnicorn, error) {
if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
return nil, err
}
unicorn := &FakeUnicorn{
pixels: makePixels(width, height),
window: nil,
renderer: nil,
displayWidth: 300,
displayHeight: 300,
}
if err := unicorn.createWindow(); err != nil {
unicorn.Close()
return nil, err
}
if err := unicorn.createRenderer(); err != nil {
unicorn.Close()
return nil, err
}
return unicorn, nil
}
func (f *FakeUnicorn) createWindow() error {
window, err := sdl.CreateWindow("Fake Unicorn",
sdl.WINDOWPOS_UNDEFINED,
sdl.WINDOWPOS_UNDEFINED,
f.displayWidth,
f.displayHeight,
sdl.WINDOW_SHOWN)
f.window = window
return err
}
func (f *FakeUnicorn) createRenderer() error {
renderer, err := sdl.CreateRenderer(f.window, -1, sdl.RENDERER_ACCELERATED)
f.renderer = renderer
return err
}
func (f *FakeUnicorn) Close() error {
if f.window != nil {
f.window.Destroy()
}
if f.renderer != nil {
f.renderer.Destroy()
}
return nil
}
func (f *FakeUnicorn) GetWidth() uint8 {
return uint8(len(f.pixels))
}
func (f *FakeUnicorn) GetHeight() uint8 {
if len(f.pixels) > 0 {
return uint8(len(f.pixels[0]))
}
return 0
}
func (f *FakeUnicorn) GetPixels() [][][]uint8 {
return f.pixels
}
func (f *FakeUnicorn) SetPixel(x, y, r, g, b uint8) {
f.pixels[x][y] = []uint8{r, g, b}
}
func (f *FakeUnicorn) Show() {
width, height := f.GetWidth(), f.GetHeight()
for x := uint8(0); x < width; x++ {
for y := uint8(0); y < height; y++ {
r, g, b := rgb(f.pixels[x][y])
if err := f.renderer.SetDrawColor(r, g, b, uint8(255)); err != nil {
panic(err)
}
cellWidth := f.displayWidth / int32(width)
cellHeight := f.displayHeight / int32(height)
if err := f.renderer.FillRect(&sdl.Rect{
X: cellWidth * int32(x),
Y: f.displayHeight - (cellHeight * int32(y)) - cellHeight, // SDL Y coordinate is from the top
W: cellWidth,
H: cellHeight,
}); err != nil {
panic(err)
}
}
}
f.renderer.Present()
}
func rgb(pixel []uint8) (uint8, uint8, uint8) {
return pixel[0], pixel[1], pixel[2]
}
func (f *FakeUnicorn) Clear() {
f.pixels = makePixels(f.GetWidth(), f.GetHeight())
}
func (f *FakeUnicorn) Off() {
f.Close()
}
func makePixels(width, height uint8) [][][]uint8 {
pixels := make([][][]uint8, width)
for x := uint8(0); x < width; x++ {
pixels[x] = make([][]uint8, height)
for y := uint8(0); y < height; y++ {
pixels[x][y] = []uint8{0, 0, 0}
}
}
return pixels
}
// RealUnicorn ...
// A real one! *gasps*
// type RealUnicorn struct {}
// // NewReal ...
// // Constructs a new real unicorn from fairy dust and sprinkles
// func NewReal() (*RealUnicorn, error) {
// return nil, errors.New("Couldn't make a real unicorn sorry")
// }
// func (u *RealUnicorn) GetWidth() int8 {
// return 0
// }
// func (u *RealUnicorn) GetHeight() int8 {
// return 0
// }
// func (u *RealUnicorn) GetPixels() [][][]int8 {
// return nil
// }
// func (u *RealUnicorn) SetPixel(x, y, r, g, b int8) {
// }
// func (u *RealUnicorn) Show() {
// }
// func (u *RealUnicorn) Clear() {
// }
// func (u *RealUnicorn) Off() {
// }
|
