Pixel Colour Again

[gareth1]

Thanks for the replies... here is a bit more detail.<br><br>The system is operating in W95, at 800x600 and in 256 colours.&nbsp;&nbsp;The target is a Pentium 2 system, with an AGP graphics card.&nbsp;&nbsp;What I require is a routine to return the colour of any pixel on the screen that I specify.<br><br>If you need any more info, let me know.<br><br>Gareth

 

[zBuilder]

Have you tried the Windows API function GetPixel??<br>This isn't really an assembler question mainly because most asm programmers don't do windows.(Accessing the Video buffer directly like you do in DOS in a NO-NO in Windoze)<br>So try the API fuction GetPixel. If it isn't fast enough for you, you'll have to try DirectX calls. (Out of MY league) Below is a site that has info on accessing Win API calls from VB:<br><A HREF="

http://www.vbapi.com/"

TARGET="_new">

http://www.vbapi.com/</A><br><br><br><br>The

GetPixel function retrieves the red, green, blue (RGB) color value of the pixel at the specified coordinates. <br><br>COLORREF GetPixel(<br><br>&nbsp;&nbsp;&nbsp;&nbsp;HDC hdc, // handle of device context&nbsp;&nbsp;<br>&nbsp;&nbsp;&nbsp;&nbsp;int XPos, // x-coordinate of pixel <br>&nbsp;&nbsp;&nbsp;&nbsp;int nYPos // y-coordinate of pixel <br>&nbsp;&nbsp;&nbsp; <br>Parameters<br><br>hdc<br><br>Identifies the device context. <br><br>nXPos<br><br>Specifies the logical x-coordinate of the pixel to be examined. <br><br>nYPos<br><br>Specifies the logical y-coordinate of the pixel to be examined. <br><br> <p> <br><a href=mailto:Kim_Christensen@telus.net>Kim_Christensen@telus.net</a><br><a href=

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[Alt255]

I don't think that will help Gareth1, zBuilder. The GetPixel function only works on a clip region. Correct me when I'm wrong, please... can it be coerced to get the RGB values from the entire screen? <p> <br><a href=mailto:InterruptX@excite.com>InterruptX@excite.com</a><br><a href=

http://vorpalcom.netfirms.com>Retrofit

Contingency Implementation</a><br>Send me suggestions or comments on my current software project.

 

[zBuilder]

Alt255:<br><br>Yes... You can get the whole screen (Minus taskbar I think) by doing the following:<br><br>zhdc = GetDC(NULL); // Get device context of the Whole screen<br>YourPixel = GetPixel(zhdc, x, y);&nbsp;&nbsp;// Get any pixel on the screen pointed by x & y<br>ReleaseDC(NULL, zhdc);<br> <p> <br><a href=mailto:Kim_Christensen@telus.net>Kim_Christensen@telus.net</a><br><a href=

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[gareth1]

Thanks!&nbsp;&nbsp;GetPixel does the job perfectly, I forgot to check the Taskbar part, but I don't need that anyway.&nbsp;&nbsp;For assembly programmers you know more about VB than the VB forums.<br><br>Gareth

 

[zBuilder]

gareth1:<br><br>Glad I could help you out.<br>Have fun!<br> <p> <br><a href=mailto:Kim_Christensen@telus.net>Kim_Christensen@telus.net</a><br><a href=

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