3D Fundamentals Texture Mapping Geometry Question
Posted: September 25th, 2020, 11:12 am
I'm at 3D Fundamentals Texture Mapping series. I don't understand "unfolding the geometry of the cube" part video.
Chili gives following code:
How to calculate the vertices and tc position?
For example ( -side,-side,-side ) and ( 1.0f,0.0f ).
I can understand when cube has 8 vertices in 3D space, but confused when cube become net (14 vertices) in 3D.
Also how to determine the order of vertices position?
Chili gives following code:
Code: Select all
CubeFolded( float size )
{
const float side = size / 2.0f;
vertices.emplace_back( -side,-side,-side ); // 0
tc.emplace_back( 1.0f,0.0f );
vertices.emplace_back( side,-side,-side ); // 1
tc.emplace_back( 0.0f,0.0f );
vertices.emplace_back( -side,side,-side ); // 2
tc.emplace_back( 1.0f,1.0f );
vertices.emplace_back( side,side,-side ); // 3
tc.emplace_back( 0.0f,1.0f );
vertices.emplace_back( -side,-side,side ); // 4
tc.emplace_back( 1.0f,1.0f );
vertices.emplace_back( side,-side,side ); // 5
tc.emplace_back( 0.0f,1.0f );
vertices.emplace_back( -side,side,side ); // 6
tc.emplace_back( 1.0f,0.0f );
vertices.emplace_back( side,side,side ); // 7
tc.emplace_back( 0.0f,0.0f );
vertices.emplace_back( -side,-side,-side ); // 8
tc.emplace_back( 1.0f,0.0f );
vertices.emplace_back( side,-side,-side ); // 9
tc.emplace_back( 0.0f,0.0f );
vertices.emplace_back( -side,-side,-side ); // 10
tc.emplace_back( 0.0f,1.0f );
vertices.emplace_back( -side,-side,side ); // 11
tc.emplace_back( 0.0f,0.0f );
vertices.emplace_back( side,-side,-side ); // 12
tc.emplace_back( 1.0f,1.0f );
vertices.emplace_back( side,-side,side ); // 13
tc.emplace_back( 1.0f,0.0f );
}
For example ( -side,-side,-side ) and ( 1.0f,0.0f ).
I can understand when cube has 8 vertices in 3D space, but confused when cube become net (14 vertices) in 3D.
Also how to determine the order of vertices position?