Graphics 320, 240, 16, 2
SeedRnd MilliSecs()

Local img = CreateImage(100, 100)
SetBuffer ImageBuffer(img)
For a = 0 To 100 Step 10
	For b = 0 To 100 Step 10
		tmp = Rand(0, 2)
		If tmp = 1 Then Color 255, 0, 0 ElseIf tmp = 2 Then Color 0, 255, 0 Else Color 0, 0, 255
		Rect a, b, 10, 10
	Next
Next

SetBuffer BackBuffer()
Repeat

Color 255, 255, 255: Text 1, 200, tmpR + ", " + tmpG + ", " + tmpB
Text 1, 214, "Click to replace green with red"

DrawImage img, 0, 0

MX = MouseX(): MY = MouseY()
If MouseDown(1) Then
	For a = 0 To 100 Step 10
		For b = 0 To 100 Step 10
			If MX >= a And MX <= a + 10 And MY >= b And MY <= b + 10 Then
				GetColor a, b
				If ColorRed() = 0 And ColorGreen() = 255 And ColorBlue() = 0 Then ; It's green, replace
					SetBuffer ImageBuffer(img)
					Color 255, 0, 0: Rect a, b, 10, 10
					SetBuffer BackBuffer()
				EndIf
			EndIf
		Next
	Next
EndIf
GetColor MX, MY
tmpR = ColorRed(): tmpG = ColorGreen(): tmpB = ColorBlue()

Flip 0: Cls
Until KeyDown(1)