' Draw to image buffer sample
'
' Last updated: <2024/02/12 01:41:58 +0900>
' License : CC0 / Public Domain

'Const SCRW = 320 : Const SCRH = 180
Const SCRW = 320 : Const SCRH = 240

#include "fbgfx.bi"
Using fb

' set screen depth
Dim As Integer sdepth = 32
Select Case Command(1)
Case "8"  : sdepth = 8
Case "16" : sdepth = 16
Case "32" : sdepth = 32
End Select

' get desktop size
Dim As Integer dispw, disph
ScreenInfo dispw, disph

' get scale (Integer)
Dim As Double dscale = dispw / SCRW
If dscale > (disph / SCRH) Then dscale = disph / SCRH

ScreenRes dispw, disph, sdepth, , GFX_NO_FRAME
Dim As Any Ptr gbuf = ImageCreate(SCRW, SCRH)

Color RGB(255, 255, 255), RGB(0, 0, 0)
cls

Const PI = 3.1415926535897932
Dim As Double angle = 0.0
Dim As Boolean running = True

' Main Loop

While running
    If Inkey <> "" Then running = False

    ' draw to image buffer
    line gbuf, (0, 0) - (SCRW - 1, SCRH - 1), RGB(30, 60, 120), BF ' clear image buffer
    
    Circle gbuf, (SCRW \ 2, SCRH \ 2), (SCRH \ 2 - 1), RGB(0, 255, 0)

    Dim As Integer x, y, r
    r = SCRH / 4
    x = (SCRW / 2 - r - 1) * Cos(angle * PI / 180.0) + (SCRW / 2)
    y = (SCRH / 2 - r - 1) * Sin(angle * PI / 180.0) + (SCRH / 2)
    Circle gbuf, (x, y), r, RGB(0, 255, 255)

    Draw String gbuf, (0, 0), Str(SCRW) & "x" & SCRH, RGB(255, 255, 255)

    ' draw to screen
    ScreenLock
    Put (0, 0), gbuf, Pset
    ScreenUnlock
    
    angle += 1.0

    sleep 10
Wend