'' examples/manual/gfx/imageinfo.bas
''
'' Example extracted from the FreeBASIC Manual
'' from topic 'IMAGEINFO'
''
'' See Also: https://www.freebasic.net/wiki/wikka.php?wakka=KeyPgImageInfo
'' --------

'' Create 32-bit graphics screen and image.
If ScreenRes(320, 200, 32) <> 0 Then
	Print "Could not set the requested graphics mode"
	Sleep
	End 1
End If

Dim image As Any Ptr = ImageCreate( 64, 64 )

If image = 0 Then
	Print "unable to create image."
	Sleep
	End 1
End If

Dim pitch As Long
Dim pixels As Any Ptr

'' Get enough information to iterate through the pixel data.
If 0 <> ImageInfo( image, ,,, pitch, pixels ) Then
	ImageDestroy image
	Print "unable to retrieve image information."
	Sleep
	End 1
End If

'' Draw a pattern on the image by directly manipulating pixel memory.
For y As Integer = 0 To 63
	Dim row As ULong Ptr = pixels + y * pitch

	For x As Integer = 0 To 63
		row[x] = RGB(x * 4, y * 4, (x Xor y) * 4)
	Next x
Next y

'' Draw the image onto the screen.
Put (10, 10), image

ImageDestroy( image )

Sleep