Hi all. This function convert world 3D coordinates into screen 2D position. Please don't ask me explain this math because English not my first language. It's too difficultly for me.
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`* Created: 22/04/2003 *
`* By: DMiTR0S dmitr0s@newmail.ru *
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`* Free License Agreement. *
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`* The user/developer agrees to include a visible credit to "Dmitry Kuschev" *
`* within your programs documentation and or web site. *
`* *
`* The user/developer agrees to NOT offer the this source code for Sale. *
`* *
`* Providing the user/Developer agrees in full to the previous Free *
`* License Agreement clauses, the user/developer may use this source *
`* code FREELY in all their products, commercial or otherwise. *
`* *
`*******************************************************************************
Make Object Sphere 1, 5
Position Object 1, Rnd(10), Rnd(10), Rnd(10)
r=Make Vector3(1)
r=Make Vector2(2)
r=Make Matrix4(3)
FOV# = 61.962
Aspectratio#=((Screen Width()*1.0)/(Screen Height()*1.0))
Sync Rate 0
Sync On
Do
Control Camera Using ArrowKeys 0, 10, 5
Set Vector3 1, Object Position X(1), Object Position Y(1), Object Position Z(1)
World3DToScreen2D(1, 2, 3, FOV#, Aspectratio#)
Text 10, 10, "Code by DMiTR0S"
Text 10, 30, "Object Screen X(1) = "+Str$(Object Screen X(1))+" Object Screen Y(1) = "+Str$(Object Screen Y(1))
Text 10, 50, "World3DToScreen2D X = "+Str$(X Vector2(2))+" World3DToScreen2D Y = "+Str$(Y Vector2(2))
Sync
Loop
Function World3DToScreen2D(Vec3D, Vec2D, MatrixTemp, FOV As Float, Aspectratio As Float)
View Matrix4 MatrixTemp
Transform Coords Vector3 Vec3D, Vec3D, MatrixTemp
Normalize Vector3 Vec3D, Vec3D
Multiply Vector3 Vec3D, 1.0/Z Vector3(Vec3D)
Set Vector2 Vec2D, Int(((1.0-(-1.0*((X Vector3(Vec3D)/Tan(FOV/2.0))/Aspectratio)))/2.0)*(Screen Width())), Int(((1.0-(Y Vector3(Vec3D)/Tan(FOV/2.0)))/2.0)*(Screen Height()))
EndFunction
