Windows API - Win32
A core set of Windows application programming interfaces (APIs) for desktop and server applications. Previously known as Win32 API.
2,422 questions
C++ - How draw an image with the 4 corners?
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Joaquim Miguel Jesus
1
Reputation point
can i draw an image(entire image) with 4 corners?
the PlgBlt() works only with 3 corners, i can't use the 4 corner :(
Windows API - Win32
C++
C++
A high-level, general-purpose programming language, created as an extension of the C programming language, that has object-oriented, generic, and functional features in addition to facilities for low-level memory manipulation.
3,526 questions
{count} votes
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Jeanine Zhang-MSFT 9,181 Reputation points Microsoft Vendor2022-04-22T01:49:21.533+00:00 According to the Doc:
The fourth vertex of the parallelogram (D) is defined by treating the first three points (A, B, and C ) as vectors and computing D = B +CA.
PlgBlt can only result in a parallelogram.
What do you mean draw an image(entire image) with 4 corners? Could you please provide some screenshots to tell us what you are trying to draw?
And I suggest you could refer to the Doc: Using a Pen to Draw Lines and Shapes
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Joaquim Miguel Jesus 1 Reputation point
2022-04-22T09:30:57.36+00:00 the image have 4 corners. now imagine if i rotate it on X, Y and Z. the distance between the TopLeft and BottomLeft can be more big than the distance between TopRight and BottomRight... unless the PlgBlt() is prepared for that
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Jeanine Zhang-MSFT 9,181 Reputation points Microsoft Vendor
2022-04-22T09:38:19.467+00:00 Whether you want to achieve is something like this : https://stackoverflow.com/questions/9608600/how-can-i-render-a-square-bitmap-to-an-arbitrary-four-sided-polygon-using-gdi
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Joaquim Miguel Jesus 1 Reputation point
2022-04-22T09:49:05.413+00:00 
is that possible with PlgBlt()? -
Castorix31 81,636 Reputation points2022-04-22T13:15:48.687+00:00 PlgBlt is for parallelograms transforms
It can be done with Direct2D
Test with Matrix4x4F :
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Joaquim Miguel Jesus 1 Reputation point
2022-04-22T13:20:58.03+00:00 i'm sorry, but what means 'parallel transforms'?
that's why i did draw a line with pixels calculation, fill with some function(too much wholes, depending on angle lol) and that's why i'm trying the Alphablend\stretch pixels calculation ;)
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Castorix31 81,636 Reputation points
2022-04-22T13:26:23.117+00:00 I meant that the result with PlgBlt is a parallelogram because of the 3 points
With a 4*4 matrix, you can do like the test I posted -
Joaquim Miguel Jesus 1 Reputation point
2022-04-22T13:28:05.063+00:00 thank you so much for all
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