From 0ac1a8d23155a27e62331f8c922b9e3bc0a36a3d Mon Sep 17 00:00:00 2001
From: Pavel Tisnovsky <ptisnovs@redhat.com>
Date: Tue, 5 May 2020 08:52:51 +0200
Subject: [PATCH] Example #12: setting global color channel values

---
 lesson7/sdl/introduction/test12.go | 57 ++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 lesson7/sdl/introduction/test12.go

diff --git a/lesson7/sdl/introduction/test12.go b/lesson7/sdl/introduction/test12.go
new file mode 100644
index 0000000..5cd63e5
--- /dev/null
+++ b/lesson7/sdl/introduction/test12.go
@@ -0,0 +1,57 @@
+package main
+
+import (
+	"github.com/veandco/go-sdl2/img"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+const (
+	width  = 640
+	height = 480
+)
+
+func main() {
+	if err := sdl.Init(sdl.INIT_VIDEO); err != nil {
+		panic(err)
+	}
+	defer sdl.Quit()
+
+	window, err := sdl.CreateWindow("SDL2 example #12", sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED,
+		width, height, sdl.WINDOW_SHOWN)
+	if err != nil {
+		panic(err)
+	}
+	defer window.Destroy()
+
+	primarySurface, err := window.GetSurface()
+	if err != nil {
+		panic(err)
+	}
+
+	image, err := img.Load("globe.png")
+	if err != nil {
+		panic(err)
+	}
+	defer image.Free()
+
+	primarySurface.FillRect(nil, sdl.MapRGB(primarySurface.Format, 192, 255, 192))
+
+	dstRect := sdl.Rect{}
+
+	for y := 0; y < 4; y++ {
+		for x := 0; x < 4; x++ {
+			image.SetColorMod(byte(x*64), 255, byte(y*64))
+			dstRect.X = int32(10 + x*100)
+			dstRect.Y = int32(10 + y*100)
+
+			err = image.Blit(nil, primarySurface, &dstRect)
+			if err != nil {
+				panic(err)
+			}
+		}
+	}
+
+	window.UpdateSurface()
+
+	sdl.Delay(5000)
+}