Defined in File Ifc4x3_rc1.h
IfcTextureVertex: public Ifc4x3_rc1::IfcPresentationItem¶
An IfcTextureVertex is a list of 2 (S, T) texture coordinates.
The following additional definitions from ISO 19775 apply:
Each vertex-based geometry node uses a set of 2D texture coordinates that map textures to vertices. Texture map values ( ImageTexture, PixelTexture) range from [0.0, 1.0] along the S-axis and T-axis. However, texture coordinate values may be in the range (-∞,∞). Texture coordinates identify a location (and thus a colour value) in the texture map. The horizontal coordinate S is specified first, followed by the vertical coordinate T. If the texture map is repeated in a given direction (S-axis or T-axis), a texture coordinate C (s or t) is mapped into a texture map that has N pixels in the given direction as follows:
Texture map location = (C - floor(C)) × N
If the texture map is not repeated, the texture coordinates are clamped to the 0.0 to 1.0 range as follows:
Texture map location = N, if C > 1.0, = 0.0, if C < 0.0, = C × N, if 0.0 ≤ C ≤ 1.0.
Texture coordinates may be transformed (scaled, rotated, translated) by supplying a TextureTransform as a component of the texture’s definition.
HISTORY: New entity in IFC 2x2.
The first coordinate is the S, the second coordinate is the T parameter value.