Moved unicorn lib to it's own package

4 files changed, 313 insertions, 0 deletions

diff --git a/unicorn/FakeUnicorn.go b/unicorn/FakeUnicorn.go
new file mode 100644
index 0000000..3236842
--- /dev/null
+++ b/unicorn/FakeUnicorn.go
@@ -0,0 +1,98 @@
+// +build linux,386 linux,amd64
+
+package unicorn
+
+import (
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+type FakeUnicorn struct {
+	BaseUnicorn
+	displayWidth  int32
+	displayHeight int32
+	window        *sdl.Window
+	renderer      *sdl.Renderer
+}
+
+// NewUnicorn ...
+// Constructs a new fake unicorn out of paint and glue
+func NewUnicorn() (*FakeUnicorn, error) {
+	width := uint8(16)
+	height := uint8(16)
+	if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
+		return nil, err
+	}
+
+	unicorn := &FakeUnicorn{
+		BaseUnicorn{
+			pixels: makePixels(width, height),
+		},
+		300,
+		300,
+		nil,
+		nil,
+	}
+	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) 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 (f *FakeUnicorn) Off() {
+	f.Close()
+}
diff --git a/unicorn/RealUnicorn.go b/unicorn/RealUnicorn.go
new file mode 100644
index 0000000..4e5c376
--- /dev/null
+++ b/unicorn/RealUnicorn.go
@@ -0,0 +1,66 @@
+// +build linux,arm linux,arm64
+
+package unicorn
+
+import (
+	//"golang.org/x/exp/io/spi"
+	"log"
+
+	"github.com/ecc1/spi"
+)
+
+type RealUnicorn struct {
+	BaseUnicorn
+	device *spi.Device
+}
+
+// NewUnicorn ...
+// Constructs a new real unicorn from fairy dust and sprinkles
+func NewUnicorn() (*RealUnicorn, error) {
+	dev, err := spi.Open("/dev/spidev0.0", 9000000, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	return &RealUnicorn{
+		BaseUnicorn{
+			pixels: makePixels(16, 16),
+		},
+		dev,
+	}, nil
+}
+
+func (u *RealUnicorn) Show() {
+	// Width * height * colours + leading bit
+	width := int(u.GetWidth())
+	height := int(u.GetHeight())
+	sz := (width * height * 3) + 1
+	write := make([]byte, sz)
+
+	// Add the leading bit
+	write[0] = 0x72
+	// Add all the pixel values
+	ix := 1
+	for x := 0; x < width; x++ {
+		for y := 0; y < height; y++ {
+			for j := 0; j < 3; j++ {
+				write[ix] = byte(u.pixels[x][y][j])
+				ix++
+			}
+		}
+	}
+	// Write to the device
+	//err := u.device.Tx(write, nil)
+	err := u.device.Transfer(write)
+	if err != nil {
+		log.Printf("Error writing to SPI device %v", err)
+	}
+}
+
+func (u *RealUnicorn) Off() {
+	u.Close()
+}
+
+func (u *RealUnicorn) Close() error {
+	return u.device.Close()
+}
diff --git a/unicorn/Unicorn.go b/unicorn/Unicorn.go
new file mode 100644
index 0000000..09f712e
--- /dev/null
+++ b/unicorn/Unicorn.go
@@ -0,0 +1,73 @@
+package unicorn
+
+// 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. Get's a real on on ARM hardware,
+// get's a fake one on x86
+func GetUnicorn() (Unicorn, error) {
+	return NewUnicorn()
+}
+
+type BaseUnicorn struct {
+	pixels [][][]uint8
+}
+
+func (f *BaseUnicorn) GetWidth() uint8 {
+	return uint8(len(f.pixels))
+}
+
+func (f *BaseUnicorn) GetHeight() uint8 {
+	if len(f.pixels) > 0 {
+		return uint8(len(f.pixels[0]))
+	}
+	return 0
+}
+
+func (f *BaseUnicorn) GetPixels() [][][]uint8 {
+	return f.pixels
+}
+
+func (f *BaseUnicorn) SetPixel(x, y, r, g, b uint8) {
+	f.pixels[x][y] = []uint8{r, g, b}
+}
+
+func (f *BaseUnicorn) Clear() {
+	f.pixels = makePixels(f.GetWidth(), f.GetHeight())
+}
+
+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
+}
+
+func rgb(pixel []uint8) (uint8, uint8, uint8) {
+	return pixel[0], pixel[1], pixel[2]
+}
diff --git a/unicorn/Unicorn_test.go b/unicorn/Unicorn_test.go
new file mode 100644
index 0000000..358dc7b
--- /dev/null
+++ b/unicorn/Unicorn_test.go
@@ -0,0 +1,76 @@
+package unicorn
+
+import (
+	"reflect"
+	"testing"
+	"time"
+)
+
+func TestFakeUnicorn(t *testing.T) {
+	unicorn, err := NewUnicorn()
+	if err != nil {
+		t.Errorf("Got an error making a fake unicorn, shouldn't happen")
+	}
+	defer unicorn.Close()
+
+	// Check simple functions
+	if unicorn.GetHeight() != 16 {
+		t.Errorf("Height was wrong, expecting 16")
+	}
+	if unicorn.GetWidth() != 16 {
+		t.Errorf("Width was wrong, expecting 16")
+	}
+	// Pixels should be black to start with
+	pixels := unicorn.GetPixels()
+	for x := uint8(0); x < 16; x++ {
+		for y := uint8(0); y < 16; y++ {
+			if !reflect.DeepEqual(pixels[x][y], []uint8{0, 0, 0}) {
+				t.Errorf("Expecting black pixels to start with")
+			}
+		}
+	}
+
+	// Should be able to set a pixel, no others should change
+	unicorn.SetPixel(0, 0, uint8(255), uint8(255), uint8(255))
+	pixels = unicorn.GetPixels()
+	if !reflect.DeepEqual(pixels[0][0], []uint8{255, 255, 255}) {
+		t.Errorf("Pixel wasn't set when it should be")
+	}
+	for x := uint8(0); x < 16; x++ {
+		for y := uint8(0); y < 16; y++ {
+			if x == 0 && y == 0 {
+				continue
+			}
+			if !reflect.DeepEqual(pixels[x][y], []uint8{0, 0, 0}) {
+				t.Errorf("Expecting black pixels to start with")
+			}
+		}
+	}
+
+	// Should be able to set a second pixel
+	unicorn.SetPixel(3, 4, uint8(4), uint8(5), uint8(6))
+	pixels = unicorn.GetPixels()
+	for x := uint8(0); x < 16; x++ {
+		for y := uint8(0); y < 16; y++ {
+			checkcolor := []uint8{0, 0, 0}
+			if x == 0 && y == 0 {
+				checkcolor = []uint8{255, 255, 255}
+			} else if x == 3 && y == 4 {
+				checkcolor = []uint8{4, 5, 6}
+			}
+			if !reflect.DeepEqual(pixels[x][y], checkcolor) {
+				t.Errorf("Got incorrect pixel color at %d %d", x, y)
+			}
+		}
+	}
+
+	unicorn.Show()
+	time.Sleep(time.Duration(500) * time.Millisecond)
+	unicorn.SetPixel(10, 10, uint8(255), uint8(255), uint8(0))
+	unicorn.Show()
+	time.Sleep(time.Duration(500) * time.Millisecond)
+
+	unicorn.SetPixel(0, 15, uint8(255), uint8(0), uint8(0))
+	unicorn.Show()
+	time.Sleep(time.Duration(500) * time.Millisecond)
+}