Color of a screen pixel: Difference between revisions

=={{header|AutoHotkey}}==

<lang AutoHotkey>PixelGetColor, color, %X%, %Y%</lang>

=={{header|AutoIt}}==

<lang autoit>Opt('MouseCoordMode',1) ; 1 = (default) absolute screen coordinates

$pos = MouseGetPos()

$c = PixelGetColor($pos[0], $pos[1])

ConsoleWrite("Color at x=" & $pos[0] & ",y=" & $pos[1] & _

" ==> " & $c & " = 0x" & Hex($c) & @CRLF)</lang>

{{Out}}

<pre>

Color at x=3,y=733 ==> 3829413 = 0x003A6EA5

</pre>

=={{header|Axe}}==

<lang axe>Disp pxl-Test(50,50)▶Dec,i</lang>

=={{header|BaCon}}==

BaCon can make use of the High Performance Canvas include. Outside this canvas it needs to access XLib API functions.

<lang qbasic>INCLUDE canvas

FULLSCREEN

color = GETINK(100, 100, 4)

WAITKEY</lang>

=={{header|BASIC}}==

==={{header|Applesoft BASIC}}===

==={{header|BBC BASIC}}===

In [[BBC BASIC for Windows]] you can read either the 'logical colour' (palette index) or the 'true colour' (24-bit RGB value).

<lang bbcbasic> palette_index% = POINT(x%, y%)

RGB24b_colour% = TINT(x%, y%)</lang>

==={{header|FreeBASIC}}===

This is a very simple example from the FreeBASIC documentation. To obtain the color of an arbitrary screen pixel (i.e. outside

the graphics screen controlled by FB) one would need to use API functions.

<lang freebasic>FB 1.05.0 Win64

' Set an appropriate screen mode - 320 x 240 x 8bpp indexed color

ScreenRes 320, 240, 8

' Draw a line using color 12 (light red)

Line (20,20)-(100,100), 12

' Print the color of a point on the line

Print Point(20,20) '' prints 12

' Sleep before the program closes

Sleep</lang>

==={{header|QuickBASIC}}===

==={{header|Integer BASIC}}===

See [[#Applesoft BASIC|Applesoft BASIC]].

==={{header|Liberty BASIC}}===

<lang lb>'This example requires the Windows API

Struct point, x As long, y As long

hDC = GetDC(0)

result = GetCursorPos()

Print GetPixel(hDC, point.x.struct, point.y.struct)

Call ReleaseDC 0, hDC

End

Sub ReleaseDC hWnd, hDC

CallDLL #user32,"ReleaseDC", hWnd As uLong, hDC As uLong, ret As Long

End Sub

Function GetDC(hWnd)

CallDLL #user32, "GetDC", hWnd As uLong, GetDC As uLong

End Function

Function GetCursorPos()

CallDLL #user32, "GetCursorPos", point As struct, GetCursorPos As uLong

End Function

Function GetPixel(hDC, x, y)

CallDLL #gdi32, "GetPixel", hDC As uLong, x As long, y As long, GetPixel As long

End Function</lang>

==={{header|Locomotive Basic}}===

<lang locobasic>10 x=320:y=200

20 color=TEST(x,y)

30 PRINT "Pen color at"; x; y; "is"; color</lang>

==={{header|PureBasic}}===

Return the color used at the x,y position in the current output. If the current output has an alpha channel then the result will be a 32bit RGBA value, otherwise it will be a 24bit RGB value. The color can be split in their RGB and alpha values by using the Red(), Green(), Blue() and Alpha() functions.

<lang PureBasic>Color = Point(x, y)</lang>

To get the colour of a pixel on the screen when it is not managed by PureBasic (ie. from other programs' windows), it is necessary to use Windows API. This works only under Windows.

<lang PureBasic>

hDC = GetDC_(0)

Color = GetPixel_(hDC, x, y)

ReleaseDC_(0, hDC)</lang>

This work fine!!

<lang PureBasic>poz.point

If OpenWindow(0,0,0,100,45,"Get pixel color at cursor position",#PB_Window_MinimizeGadget)

TextGadget(0,0,0,50,12,"Red: ")

TextGadget(1,0,15,50,12,"Green: ")

TextGadget(2,0,30,50,12,"Blue: ")

TextGadget(3,50,0,50,12,"")

TextGadget(4,50,15,50,12,"")

TextGadget(5,50,30,50,12,"")

hDC = GetDC_(0)

Repeat

oldx=poz\x

oldy=poz\y

GetCursorPos_(@poz)

Color = GetPixel_(hDC, poz\x, poz\y)

If poz\x<>oldx Or poz\y<>oldy

SetGadgetText(3,Str(Red(color)))

SetGadgetText(4,Str(Green(color)))

SetGadgetText(5,Str(Blue(color)))

EndIf

event=WaitWindowEvent(200)

Until event=#PB_Event_CloseWindow

ReleaseDC_(0, hDC)

EndIf</lang>

==={{header|SmileBASIC}}===

<lang smilebasic>DEF GETPX X,Y OUT R,G,B

PCOL=GSPOIT(X,Y)

RGBREAD PCOL OUT R,G,B

END</lang>

==={{header|TI-89 BASIC}}===

Only the graph screen can be read.

<lang ti89b>pxlTest(y, x) © returns boolean</lang>

==={{header|Visual Basic .NET}}===

<lang vbnet> Private Function GetPixelColor(ByVal Location As Point) As Color

Dim b As New Bitmap(1, 1)

Dim g As Graphics = Graphics.FromImage(b)

g.CopyFromScreen(Location, Point.Empty, New Size(1, 1))

Return b.GetPixel(0, 0)

End Function</lang>

==={{header|VBA}}===

In "pure" Visual Basic for Application, there is no way to find the color of a screen pixel.

We have to use api's functions.

This code should be adapted for 64 bits versions...

<lang vb>

Option Explicit

Private Type POINTAPI

x As Long

y As Long

End Type

Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long) As Long

Private Declare Function GetCursorPos Lib "USER32" (lpPoint As POINTAPI) As Long

Private Declare Function GetWindowDC Lib "USER32" (ByVal hWnd As Long) As Long

Sub Color_of_a_screen_pixel()

Dim myColor As Long

myColor = Get_Color_Under_Cursor

End Sub

Function Get_Color_Under_Cursor() As Long

Dim Pos As POINTAPI, lngDc As Long

lngDc = GetWindowDC(0)

GetCursorPos Pos

Get_Color_Under_Cursor = GetPixel(lngDc, Pos.x, Pos.y)

End Function

</lang>

==={{header|Yabasic}}===

<lang Yabasic>open window 100, 100

backcolor 255, 0, 0

clear window

color 0, 255, 0

fill rectangle 50, 50, 75, 75

x = 60 : y = 60

s$ = right$(getbit$(x, y, x, y), 6)

blue = dec(right$(s$, 2))

green = dec(mid$(s$, 3, 2))

red = dec(left$(s$, 2))

print red, " ", green, " ", blue</lang>

==={{header|ZX Spectrum Basic}}===

The built-in function <code>POINT (x,y)</code> returns 0 if the pixel at <tt>x,y</tt> is set to the relevant <code>PAPER</code> colour, or 1 if it is set to the <code>INK</code> colour. (Note that there can only be a maximum of two colours in each 8x8-pixel section of the screen.)

=={{header|Lingo}}==