examples: add shaped-window example

Signed-off-by: Lilis Iskandar <lilis@veand.co>

examples/shaped-window/go.mod

@@ -0,0 +1,7 @@
+module shaped-window
+
+go 1.20
+
+require github.com/veandco/go-sdl2 v0.4.30
+
+replace github.com/veandco/go-sdl2 v0.4.30 => github.com/TooManySugar/go-sdl2 v0.0.0-20230201111233-54995b38d528

examples/shaped-window/go.sum

@@ -0,0 +1,2 @@
+github.com/TooManySugar/go-sdl2 v0.0.0-20230201111233-54995b38d528 h1:0h3DcRpKTWP9WtAPhNKEt1TSi3Ra3vCDEHDIA8n3rzw=
+github.com/TooManySugar/go-sdl2 v0.0.0-20230201111233-54995b38d528/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=

examples/shaped-window/main.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"fmt"
+	"image"
+	"image/png"
+	"os"
+
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+func fatal(msgs ...interface{}) {
+	fmt.Fprint(os.Stderr, msgs...)
+	os.Exit(1)
+}
+
+func main() {
+	reader, err := os.Open("../../assets/test.png")
+	if err != nil {
+		fatal(err)
+	}
+	defer reader.Close()
+
+	img, err := png.Decode(reader)
+	if err != nil {
+		fatal(err)
+	}
+
+	imgNRGBA, ok := img.(*image.NRGBA)
+	if !ok {
+		fatal("failed to cast img to image.NRGBA")
+	}
+
+	bounds := imgNRGBA.Bounds()
+
+	var width, height int32
+
+	width = int32(bounds.Max.X - bounds.Min.X)
+	height = int32(bounds.Max.Y - bounds.Min.Y)
+
+	surf, err := sdl.CreateRGBSurfaceWithFormat(0, width, height, 32, uint32(sdl.PIXELFORMAT_ABGR8888))
+	if err != nil {
+		fatal(err)
+	}
+	defer surf.Free()
+
+	surf.Lock()
+
+	if len(surf.Pixels()) != len(imgNRGBA.Pix) {
+		fatal("surface and image had different pixel size")
+	}
+
+	copy(surf.Pixels(), imgNRGBA.Pix)
+
+	surf.Unlock()
+
+	if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
+		fatal(err)
+	}
+	defer sdl.Quit()
+
+	window, err := sdl.CreateShapedWindow(
+		"gopher",
+		uint32(sdl.WINDOWPOS_CENTERED), uint32(sdl.WINDOWPOS_CENTERED),
+		uint32(width), uint32(height),
+		sdl.WINDOW_SHOWN)
+	if err != nil {
+		fatal(err)
+	}
+	defer window.Destroy()
+
+	renderer, err := sdl.CreateRenderer(window, -1, sdl.RENDERER_SOFTWARE)
+	if err != nil {
+		fatal(err)
+	}
+	defer renderer.Destroy()
+
+	shmp := sdl.ShapeModeBinarizeAlpha{1 << 6}
+
+	window.SetShape(surf, shmp)
+
+	texture, err := renderer.CreateTextureFromSurface(surf)
+	if err != nil {
+		fatal(err)
+	}
+	defer texture.Destroy()
+
+	renderer.Copy(texture, nil, nil)
+
+	renderer.Present()
+
+eventLoop:
+	for {
+		event := sdl.WaitEvent()
+		if event == nil {
+			break eventLoop
+		}
+
+		switch e := event.(type) {
+		case *sdl.QuitEvent:
+			fmt.Println("Close")
+			break eventLoop
+
+		case *sdl.MouseButtonEvent:
+			if e.Button == sdl.BUTTON_LEFT && e.State == sdl.PRESSED {
+				fmt.Println("LMB Click")
+				break eventLoop
+			}
+
+			if e.Button == sdl.BUTTON_RIGHT && e.State == sdl.PRESSED {
+				fmt.Println("RMB Click")
+				fmt.Println("window.IsShaped():", window.IsShaped())
+				wsm, ierr := window.GetShapeMode()
+				fmt.Println("window.GetShapeMode():", wsm, ierr)
+			}
+		}
+	}
+
+	fmt.Println("Quit")
+}