The pattern describes a mesh to generate: positions of
- nodes within a geometrical domain and nodal connectivity of elements.
- As well, a pattern specifies the so-called key-points, i.e. nodes that
- will be located at geometrical vertices. Pattern description is stored
- in <pattern_name>.smp file.
- -
The smp file contains 4 sections:
- -- -
1. The first line holds the number of nodes - (N).
- -- -
2. The next N lines describe nodes coordinates. - Each line holds 2 coordinates of a node.
- -- -
3. A key-points line: indices of nodes to - be mapped on geometrical vertices. An index n refers to a node described - on an n-th line of section 2. The first node index is zero.
- -- -
4. The rest lines describe nodal connectivity - of elements, one line for an element. A line holds indices of nodes forming - an element. An index n refers to a node described on an n-th line of the - section 2. The first node index is zero. There must be 3 or 4 indices - on a line: only 2d elements are allowed.
- -- -
The 2D pattern must contain at least one element and at least one key-point. - All key-points must lay on boundaries.
- -- -
An example of a simple smp file and a preview of a pattern described - in this file:
- -- -
- -
- -
To apply pattern mapping to a geometrical object:
- -- -
1. From the Modification
- menu choose the Pattern Mapping
- item or click 
button in the toolbar. The following
- dialog box shall appear:
- -
|
-
|
-
-
|
- -
To apply a pattern to a geometrical object, you should specify:
- -- a face having the number of vertices equal - to the number of key-points in the pattern; the number of key-points on - internal boundaries of a pattern must also be equal to the number of vertices - on internal boundaries of a face;
- -- a vertex to which the first key-point should - be mapped,
- -- reverse or not the order of key-points. - (The order of vertices of a face is counterclockwise looking from outside).
- -- -
Then you either load a .smp pattern file previously created manually
- by clicking on the 
button, or click on the New
- button for automatic generation.
For an automatic generation you just specify a geometrical face having - a mesh built on it. Mesh nodes lying on face vertices become key-points. - Additionally, you may choose the way of getting nodes coordinates by projecting nodes on the face instead - of using "positions on face" generated by mesher (if there is - any). Faces having a seam edge cant be used for automatic pattern creation.
- -- -
When creating a pattern from an existing mesh, there are two possible - cases:
- -- -
1. A sub-mesh on face is selected. A pattern is created from the 2d - elements bound to a face by mesher. Node coordinates are either "positions - on face" computed by mesher, or coordinates got by node projection - on a geometrical surface, according to your choice.
- -2. A mesh where the main shape is a face, is selected. A pattern is - created from all the 2d elements in a mesh. If all mesh elements are build - by mesher, the user can select the way of getting nodes coordinates, else - all nodes are projected on a face surface.
- -|
-
|
-
-
|
- -
The mapping algorithm is as follows:
- -- -
1. Key-points are set in the order that they - are encountered when walking along a pattern boundary so that elements - are on the left. The first key-point is preserved.
- -2. Find geometrical vertices corresponding - to key-points by vertices order in a face boundary; here, "Reverse - order of key-points" flag is taken into account.
- -- -
- -
3. Boundary nodes of a pattern are mapped - onto edges of a face: a node located between certain key-points on a pattern - boundary is mapped on a geometrical edge limited by corresponding geometrical - vertices. Node position on an edge reflects its distance from two key-points.
- -- -
- -
4. Coordinates of a non-boundary node in - a parametric space of a face are defined as following. In a parametric - space of a pattern, a node lays at the intersection of two iso-lines, - each of which intersects a pattern boundary at least at two points. Knowing - mapped positions of boundary nodes, we find where isoline-boundary intersection - points are mapped to, and hence we can find mapped isolines direction - and then, two node positions on two mapped isolines. The eventual mapped - position of a node is found as an average of positions on mapped isolines.
- -- -
- -
See - Also a sample TUI Script of a Pattern - Mapping operation.
- -- - - - + + + + + +
The pattern describes a mesh to generate: positions of
+ nodes within a geometrical domain and nodal connectivity of elements.
+ As well, a pattern specifies the so-called key-points, i.e. nodes that
+ will be located at geometrical vertices. Pattern description is stored
+ in <pattern_name>.smp file.
+ +
The smp file contains 4 sections:
+ ++ +
1. The first line holds the number of nodes + (N).
+ ++ +
2. The next N lines describe nodes coordinates. + Each line holds 2 coordinates of a node.
+ ++ +
3. A key-points line: indices of nodes to + be mapped on geometrical vertices. An index n refers to a node described + on an n-th line of section 2. The first node index is zero.
+ ++ +
4. The rest lines describe nodal connectivity + of elements, one line for an element. A line holds indices of nodes forming + an element. An index n refers to a node described on an n-th line of the + section 2. The first node index is zero. There must be 3 or 4 indices + on a line: only 2d elements are allowed.
+ ++ +
The 2D pattern must contain at least one element and at least one key-point. + All key-points must lay on boundaries.
+ ++ +
An example of a simple smp file and a preview of a pattern described + in this file:
+ ++ +
+ +
+ +
To apply pattern mapping to a geometrical object:
+ ++ +
1. From the Modification
+ menu choose the Pattern Mapping
+ item or click button in the toolbar. The following
+ dialog box shall appear:
+ +
|
+
|
+
+
|
+ +
To apply a pattern to a geometrical object, you should specify:
+ +- a face having the number of vertices equal + to the number of key-points in the pattern; the number of key-points on + internal boundaries of a pattern must also be equal to the number of vertices + on internal boundaries of a face;
+ +- a vertex to which the first key-point should + be mapped,
+ +- reverse or not the order of key-points. + (The order of vertices of a face is counterclockwise looking from outside).
+ ++ +
Then you either load a .smp pattern file previously created manually
+ by clicking on the button, or click on the New
+ button for automatic generation.
For an automatic generation you just specify a geometrical face having + a mesh built on it. Mesh nodes lying on face vertices become key-points. + Additionally, you may choose the way of getting nodes coordinates by projecting nodes on the face instead + of using "positions on face" generated by mesher (if there is + any). Faces having a seam edge cant be used for automatic pattern creation.
+ ++ +
When creating a pattern from an existing mesh, there are two possible + cases:
+ ++ +
1. A sub-mesh on face is selected. A pattern is created from the 2d + elements bound to a face by mesher. Node coordinates are either "positions + on face" computed by mesher, or coordinates got by node projection + on a geometrical surface, according to your choice.
+ +2. A mesh where the main shape is a face, is selected. A pattern is + created from all the 2d elements in a mesh. If all mesh elements are build + by mesher, the user can select the way of getting nodes coordinates, else + all nodes are projected on a face surface.
+ +|
+
|
+
+
|
+ +
The mapping algorithm is as follows:
+ ++ +
1. Key-points are set in the order that they + are encountered when walking along a pattern boundary so that elements + are on the left. The first key-point is preserved.
+ +2. Find geometrical vertices corresponding + to key-points by vertices order in a face boundary; here, "Reverse + order of key-points" flag is taken into account.
+ ++ +
+ +
3. Boundary nodes of a pattern are mapped + onto edges of a face: a node located between certain key-points on a pattern + boundary is mapped on a geometrical edge limited by corresponding geometrical + vertices. Node position on an edge reflects its distance from two key-points.
+ ++ +
+ +
4. Coordinates of a non-boundary node in + a parametric space of a face are defined as following. In a parametric + space of a pattern, a node lays at the intersection of two iso-lines, + each of which intersects a pattern boundary at least at two points. Knowing + mapped positions of boundary nodes, we find where isoline-boundary intersection + points are mapped to, and hence we can find mapped isolines direction + and then, two node positions on two mapped isolines. The eventual mapped + position of a node is found as an average of positions on mapped isolines.
+ ++ +
+ +
See + Also a sample TUI Script of a Pattern + Mapping operation.
+ ++ + + +
