How can i get color type from x,y coordinate by a D3D full-screen program?
i would like to determine if a x,y point is red 255
thanks in advance.
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possible duplicate http://stackoverflow.com/questions/120066/doing-readback-from-direct3d-textures-and-surfaces – dowhilefor Sep 17 '13 at 11:15
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@dowhilefor no it isn't... but just read D3D API dude, what you want to do is simply read out the frame buffer. – dhein Sep 17 '13 at 11:20
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sorry, i don't understand the meaning, can you give me a sample for only detect color? thanks! – Johnson Martin Sep 17 '13 at 11:20
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Since you have not specify DX version, there is only brief step-by-step algorithm
1) Render your scene to texture
2) Transfer tetxure back from GPU to CPU
3) Fill data from tetxure to memory buffer
5) Recalculate x, y to match tetxure resolution. Rendering window dimension can be different from DX device resolution (you can render smaller texture to bigger window and vice versa)
4) Do lookup at position [x,y]
If you are asking, how to get pixel color from 3rd party DX program, you will have to somehow take "screenshot" of application and search for color in it
Martin Perry
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Thanks, i am using d3d8. is there any code sample like your steps? – Johnson Martin Sep 17 '13 at 12:06
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Why on earth are you using d3d8? That's 13 years old and a completely unsupported API. At least use dx9, which is still being updated. – Pod Sep 17 '13 at 13:07
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Sorry, it is because my program is old and i don't want to change it to dx9. I have to waste too much times to upgrade it. – Johnson Martin Sep 17 '13 at 13:14
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Eh.. in that way I am sorry, I know nothing about DX8. I started with DX9 – Martin Perry Sep 17 '13 at 13:25
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Ok, i just convert everything to DX9, could you give me a dx9 sample code? thanks! – Johnson Martin Sep 21 '13 at 09:41