# Basic Techniques ## Building elements, basic building elements, additional building elements By combining the model area and the combined element type, the **basic building element** is defined. For example, for inputs in wall construction, this is the current wall. At the same time, with the combined element, components can also be inserted into other building elements. If, in addition to the basic building element, other building elements are also used in a combined element, these are the **additional building elements**. Additional building elements are used for inserting components, library elements, partial drawings, dimensions, and labels. ### Basic building elements | Model area | Input function | basic building element | | ----------------- | --------------------- | ---------------------- | | Floor plan | in the floor plan | current storey | | | along wall edge | selected wall | | | along truss edge | selected truss | | wall construction | on the front side | current wall | | | on the rear side | current wall | | | at points, components | current wall | | slab construction | in the floor plan | current slab field | | | at points, components | current slab field | | roof | in the floor plan | current roof | | | along truss edge | selected truss | | | in roof surface | selected roof surface | | | at points, components | current roof | | truss | on the front side | current truss | | | on the rear side | current truss | | | at points, components | current truss | | Free construction | at points, components | Free construction | ### Additional building elements For the "insert into" function of the various elements, the following options are available: 1 storey 2 roof 3 wall 4 partner wall 5 slab (current, bottom) 6 slab top 7 roof surface 8 truss 9 DICAM: Free construction If the desired building element is not the basic building element, then it is an additional building element that must first be determined. There are various procedures for this, depending on the model area, basic building element, and combined element type. For the combined element type "at points, components", the determination is performed differently than for the other combined element types and is therefore listed separately at the end. #### Additional building elements: storey * In the model areas floor plan, wall construction, and slab construction, the current storey is clearly defined. * If a truss is the basic building element and belongs to a storey, that storey is defined as an additional building element. This is independent of the model area. * In the roof model area when inserting into the floor plan: The current storey from model area floor plan. * In the roof model area when inserting into roof surface: Starting from the insertion point in the roof surface, search for the storey whose lower edge lies nearest below the insertion point. * If a truss is the basic building element and belongs to a roof, then the storey is searched for at the insertion point: it is the storey whose lower edge lies nearest below the insertion point. #### Additional building elements: roof * At present, the current roof is clearly defined in all model areas, since only one roof can exist. #### Additional building elements: wall * The wall can only be treated as an additional building element for the combined element type "at points, components". See rules below. #### Additional building elements: partner wall * A partner wall can only be found automatically if the basic building element is a wall. Thus, only for the combined element types "insert into wall" and "insert into wall view". * The search for the partner wall takes place in the plan view. * All walls of the current storey are considered. * The walls do not need to be connected to the current wall via a wall corner or T-joint. * From the origin of the insertion coordinate system, the nearest other wall is searched for. * As partner walls, walls are found that lie as if at a wall corner or a T-joint. But also walls that lie in extension of the current wall or parallel to it. * For combined elements in the connection of wall and partner wall, some special system variables are available: **SP00X:** In the wall, this is the distance in the X direction from the insertion coordinate system to the intersection of layer 0 of the two walls. For the current wall, when entering from the front side, the front side of layer 0 is used; when entering from the rear side, the rear side of layer 0 is used. In the partner wall, the front side of layer 0 is always used. **WWXY:** Angle of the wall X-axes in the XoY plane measured from the wall to the partner wall. A clockwise angle gives an angle between 0° and -180°; a counterclockwise angle (mathematically positive) between 0° and +180°. When entering from the rear side, the rotated coordinate system of the wall is used as reference. **WELR:** Indicates which end of the wall is closer to the insertion coordinate system: left = -1 (= wall start), right = +1 (= wall end). When entering from the rear side, the rotated coordinate system of the wall is used as reference; left = -1 is then the actual wall end. **A\_SP00X:** In the partner wall, this is the distance in the X direction from the projected insertion coordinate system to the intersection of layer 0 of the two walls. For the current wall, when entering from the front side, the front side of layer 0 is used; when entering from the rear side, the rear side of layer 0 is used. In the partner wall, the front side of layer 0 is always used. **A\_WELR:** Indicates which end of the wall is closer to the insertion coordinate system: left = -1, right = +1. In the partner wall, inputs are always made from the front side. * For the combined element type "at points, components", a partner wall can be determined via query bodies. See rules below. #### Additional building elements: slab (current, bottom) * The term "current" means that, at this moment, the slab is the basic building element. If the slab is required as an additional building element, then the "lower slab" is searched for here. * For this purpose, the corresponding slab field is searched for at the origin of the insertion coordinate system according to specific rules. For insertion in the floor plan, this is directly at the origin of the insertion coordinate system. For insertions in a wall or truss, the search at the origin of the insertion coordinate system is performed at a small distance in front of or behind the building element. Thus, if input is made on the front side of the wall, a slab field that ends at the rear side or within the wall is ignored. * Model areas floor plan, wall construction, roof, truss: If slab fields are present, the slab field is determined as follows: from the slab fields found at the insertion point whose upper edge lies within the range lower edge of current storey plus/minus 1.00 m, the uppermost slab is taken. All slab fields in this range are included, regardless of which storey they belong to. * For combined elements in connection with slab (current, bottom), special system variables are available: **LDp0Z:** At the origin of the insertion coordinate system, the upper edge of layer 0 of the slab (current, bottom) is searched for. This is the Z value of the upper edge. #### Additional building elements: slab top * The upper slab is searched for similarly to the lower slab at the origin of the insertion coordinate system. For insertion in the floor plan, this is directly at the origin of the insertion coordinate system. For insertions in a wall or truss, the search at the origin of the insertion coordinate system is performed at a small distance in front of or behind the building element. Thus, if input is made on the front side of the wall, a slab field that ends at the rear side or within the wall is ignored. * Model areas floor plan, wall construction, roof, truss: If slab fields are present, the slab field is determined as follows: from the slab fields found at the insertion point whose upper edge lies within the range lower edge of current storey plus 1.00 m and above, the lowest slab is taken. All slab fields in this range are included, regardless of which storey they belong to. * Model area slab construction: No upper slab is considered. * For combined elements in connection with slab top, special system variables are available: **LOp0Z:** At the origin of the insertion coordinate system, the upper edge of layer 0 of the upper slab is searched for. This is the Z value of the upper edge. #### Additional building elements: roof surface * The roof surface is searched for similarly to the upper slab at the origin of the insertion coordinate system. For insertion in the floor plan, this is directly at the origin of the insertion coordinate system. For insertions in a wall or truss, the search at the origin of the insertion coordinate system is performed at a small distance in front of or behind the building element. Thus, if input is made on the front side of the wall, a roof surface that ends at the rear side or within the wall is ignored. * Model areas floor plan, wall construction, roof, truss: If roof surfaces are present, the roof surface is determined as follows: from the roof surfaces found at the insertion point, the lowest roof surface is taken. * For combined elements in connection with roof surfaces, special system variables are available: **LFp0Z:** At the origin of the insertion coordinate system, the upper edge of layer 0 of the roof surface is searched for. This is the Z value of the upper edge. #### Additional building elements: truss * The truss can only be treated as an additional building element for the combined element type "at points, components". See rules below. #### Additional building elements: DICAM: Free construction * Free construction is always available unambiguously. #### Additional building elements: combined element type at points, components * In these combined elements, wall, partner wall, slab (current, lower), roof surface, storey, and roof can also be used simultaneously as additional building elements. * Query bodies have the highest priority in determining the additional building elements: * The first query body belonging to a wall determines the wall. The second query body belonging to a wall determines the partner wall. * The first query body belonging to a slab field, truss, or roof surface determines the slab (current, lower), truss, or roof surface respectively. An "upper slab" cannot be determined. * The first query body belonging to a roof surface or roof determines the roof. * The first query body belonging to a wall, slab field, or truss also determines the storey at the same time. The truss can only be used for this if it belongs to a storey. * Query bodies that must be selected anyway for the combined element also determine the additional building elements at the same time. In such combined elements, however, query bodies may also be useful that determine only additional building elements. Wall bodies, slab-layer or roof-layer plates can also be selected here. * Building elements not determined via query bodies can now still be adopted from the current building MOS: * If the current building MOS is defined by a wall, then this wall is the additional building element for wall, and its storey is the additional building element for storey. * Analogously, the rule also applies to slab fields and trusses that belong to a storey. * No storey can be defined via other trusses and roof surfaces. ## Coordinate systems When inserting a combined element, various coordinate systems are used one after another. Their properties and dependencies are fundamental for creating combined elements. ### Basic and insertion coordinate system, general workflow By combining the model area and the combined element type, the **Basic coordinate system** defined. For example, in the floor plan this is the coordinate system of the storey, in the wall that of the wall. See the table below for a list of the basic coordinate systems. In the basic coordinate system, the **insertion coordinate system** is defined. There are fundamentally two ways to do this: 1\. Positioning point * The origin of the insertion coordinate system is placed at a positioning point and its orientation is parallel to the basic coordinate system. * If, for positioning point = select in the preview, the displayed origin is not selected, the insertion coordinate system is shifted accordingly to the selected point. Example: A component 2.0 m long lies with its start at the displayed origin. For positioning, a point at its end is selected. If the positioning point is then chosen in the structure, the insertion coordinate system is placed 2.0 m away from the positioning point. * The Z position (height) of the origin depends on the selected option for "insertion point height". * During insertion, a rotation (base angle in XoY) relative to the basic coordinate system can be specified. In addition, when positioning point = select in preview, the orientation (also the base angle in XoY) can be rotated in 90° increments. * Cannot be used for combined element type "at points, components". 2\. Insertion coordinate system via 3 points * The insertion coordinate system is defined by 3 points:\ 1\. Origin\ 2\. Point in the direction of the X-axis\ 3\. Point in the positive ZoX plane. * Direct numbers or formulas can be used here. Variables, coordinates of query points, and coordinates of query bodies can be used. * The coordinates of the 3 points are defined in the basic coordinate system. This must also be considered in formulas. All other specifications in the combined element refer to the insertion coordinate system. * Can be used for combined element type "at points, components" and for other combined element types when "positioning point" is set to "no query". In the combined element, all further coordinate specifications then refer to the insertion coordinate system. ### Basic coordinate systems for different situations
Model areaInput functionBasic coordinate system
Floor planin the floor planglobal coordinate system
along wall edge
> wall front side
> wall rear side		wall coordinate system
wall coordinate system rear side
along truss edge
> truss front side
> truss rear side		truss coordinate system
truss coordinate system rear side
wall constructionon the front sidewall coordinate system
on the rear sidewall coordinate system rear side
at points, componentswall coordinate system
slab constructionin the floor planslab coordinate system
at points, componentsslab coordinate system
roofin the floor planglobal coordinate system
along truss edge
> truss front side
> truss rear side		truss coordinate system
truss coordinate system rear side
in roof surfaceroof surface coordinate system
at points, componentsglobal coordinate system
trusson the front sidetruss coordinate system
on the rear sidetruss coordinate system rear side
at points, componentstruss coordinate system
Free constructionat points, componentsglobal coordinate system
\* On the rear sides of walls and trusses, a modified coordinate system is used: when viewing the rear side, the X-axis runs from the wall end to the wall start, i.e. opposite to the X-axis of the normal wall coordinate system. The Y-axis runs from the rear side to the front side, thus also opposite to the normal Y-axis. The Z-axis runs, as usual, from bottom to top. When inserting on the rear side, the rear side is also used instead of the front side of layers. In addition, the meaning of system variable WELR is reversed: normally, the start of the wall is on the left and thus -1; on the rear side, the end of the wall is on the left and thus -1. Wall coordinate system: if viewed in the viewing direction toward the wall (i.e. toward the front side), the X-axis runs from left to right, the Z-axis from bottom to top, and the Y-axis from front to back. The wall body lies with its left, lower, front point at the origin of the coordinate system. for windows and doors: First, the insertion coordinate system is the same as that of the wall (basic coordinate system) and is then shifted and rotated by the subsequent parameters. See chapter: [Combined elements - insertion - for door, window](https://word2md.com/#_Kombielemente_-_Einf%C3%BCgung). Slab coordinate system: The Z-axis runs globally from bottom to top. The coordinate system is positioned so that all slab-layer plates lie in the first octant (+X and +Y). Thus, the coordinate system lies on the underside of the slab-layer plates. The Y direction is specified as the orientation when entering the slab via 2 points. Roof surface coordinate system: The X-axis runs along the eaves, thus parallel to the global XoY plane. The Y-axis runs parallel to the fall lines of the roof surface. The Z-axis runs perpendicular to the roof surface from bottom to top. The coordinate system is positioned so that the centering polygon lies at Z = 0 and all lines lie in the first octant (+X and +Y). Truss coordinate system: if viewed in the viewing direction toward the truss (i.e. toward the front side), the X-axis runs from left to right, the Z-axis from bottom to top, and the Y-axis from front to back. The truss contour lies with its left, lower point at the origin of the coordinate system. The thickness of the truss begins at Y=0; the truss contour lies at Y=thickness/2. ### Intermediate values when calculating coordinates for insertion coordinate systems Depending on the situation, complex calculations for the coordinates of the insertion coordinate system may be necessary. Then it is helpful to be able to use intermediate values. This is possible through the following sequence when executing a combined element. The logic of the sequence must be considered when creating the combined element: 1.1 All coordinates of query points, query bodies, layer contours, etc. are determined in the basic coordinate system. 1.2 Intermediate values are calculated and, where applicable, take these coordinates relative to the basic coordinate system into account. 1.3 Create the insertion coordinate system; if necessary using the intermediate values. 1.4 All coordinates of query points, query bodies, layer contours, etc. are now determined in the insertion coordinate system. 1.5 Intermediate values are calculated again and, where applicable, take these coordinates relative to the insertion coordinate system into account. 1.6 Continue executing the combined element. (17.01) If automatically searched query bodies are used in the combined element, additional steps are performed. This is necessary in order to be able to calculate the coordinates of the reference point using intermediate values and to use the found query bodies to define the insertion coordinate system: 1.1 All coordinates of query points, query bodies, layer contours, etc. are determined in the basic coordinate system. 1.2 Intermediate values are calculated and, where applicable, take these coordinates relative to the basic coordinate system into account. Values from automatically searched query bodies are still missing. 1.2a Determine the reference points; if necessary using the intermediate values. The query bodies are searched using the reference points. 1.2b Intermediate values are calculated again and continue to take coordinates relative to the basic coordinate system into account. The values of automatically searched query bodies are now also available. 1.3 Create the insertion coordinate system; if necessary using the intermediate values. 1.4 All coordinates of query points, query bodies, layer contours, etc. are now determined in the insertion coordinate system. 1.5 Intermediate values are calculated again and, where applicable, take these coordinates relative to the insertion coordinate system into account. 1.6 Continue executing the combined element. ### Translations and projections of insertion coordinate systems Insertion of components: * The insertion points of the component are always determined in the insertion coordinate system. * If components are created in a layer and parallel to the building element, the determined insertion points for the component are projected perpendicularly onto the front side of the layer. * The component is then created point by point; translations and rotations therefore depend on the situation of the projected points. This must be observed in particular for the tilt angle. * If input is made on the rear side of a wall or a truss, the points are projected onto the rear side of the layer. As described above, the basic coordinate system on the rear side differs from that on the front side. * If the wall or truss is an additional building element, the process always uses the front side, i.e. the points are projected onto the front side of the layer. Insertion of library elements: * Translation and rotation of the library element occur in the insertion coordinate system when "orientation = free" is set. * If library elements are inserted into a layer and parallel to the building element, a projected insertion coordinate system is created first: * The insertion point of the library element is projected as the origin of the projected insertion coordinate system onto the front side of the layer. * For storey, roof, and free construction: The X-axis of the insertion coordinate system is projected into the XoY plane. The Z-axis of the projected insertion coordinate system should be parallel to the Z-axis of the building element. This also defines the Y-axis. If the X-axis of the insertion coordinate system is parallel to the Z-axis of the building element, then the Y-axis is used instead. * For walls and trusses: The Z-axis of the insertion coordinate system is projected into the layer. The Y-axis of the projected insertion coordinate system should be parallel to the Y-axis of the building element. This also defines the X-axis. If the Z-axis of the insertion coordinate system is parallel to the Y-axis of the building element, then the X-axis is used instead. * For slabs and roof surfaces: The X-axis of the insertion coordinate system is projected into the layer. The Z-axis of the projected insertion coordinate system should be parallel to the Z-axis of the building element. This also defines the Y-axis. If the X-axis of the insertion coordinate system is parallel to the Z-axis of the building element, then the Y-axis is used instead. * The library element is then inserted at the origin of the projected insertion coordinate system and translated according to the offsets and rotated according to the angles. Translation and rotation therefore refer to the projected coordinate system. * If input is made on the rear side of a wall or a truss, the rear side of the layer and the coordinate system from the rear side are used accordingly. * If the wall or truss is an additional building element, the process always uses the front side. Insertion of partial drawings, dimensions, and labels: * The points to be dimensioned are projected onto the respective drawing plane. * The positioning and reference points of texts and labels are projected onto the respective drawing plane. * The X-axis of the insertion coordinate system is projected onto the drawing plane and defines the X direction for the drawing elements. The Y-axis in the drawing plane is thus also defined. * Translations and rotations refer to the projected axes. ## Temporary volumes in combined elements (from version 13.04) When executing combined elements, volumes are used that are no longer needed at the end or may even interfere. This is especially the case when the volume is used only to position a type 4 machining operation or, in a hard-soft intersection, serves only as a cutting body. * If this volume has the identifier TEMPORARY, it is automatically deleted after the combined element has been executed; the resulting type 5 machinings remain as type 0 machinings. * The identifier TEMPORARY can already be assigned to the library part or can be assigned in the combined element. Newly created components can also receive this identifier. * If the combined element is recalculated, the temporary volume is used again, transfers its machinings, and is then removed again at the end. * Note: The identifier TEMPORARY does not need to be created in the component catalog. ## Temporary plane elements as notes when entering windows and doors (24.01) Drawing elements including dimensions and texts are displayed in the preview during window entry. This is useful for providing notes during entry. However, these notes should no longer appear in the final inserted window. For this purpose, the TEMPORARY layer has now been introduced: * Plane elements located on the TEMPORARY layer are shown in the preview in the input dialog. After insertion into the structure, they are no longer displayed. * This applies to all plane elements (lines, circles, ... , dimensions, texts) created in the combined element via "partial drawings", "dimensions", and "texts, labels". * Special use of partial drawings: * In the preview, the layer settings from the first read partial drawing are adopted. This applies to color, line type, and line weight, as well as the scale of the layer. To be able to set the scale, the partial drawing should be taken from the structure, not from the plan. * From the imported partial drawing, only the plane elements of the TEMPORARY layer are removed after insertion; the other plane elements remain. Accordingly, these can be mixed within a partial drawing. ## Variables and intermediate values of combined elements in openings (doors, windows, and niches) (from version 18.01) In doors and windows, the first combined element largely determines the properties and the construction. Therefore, its variables and intermediate values are passed on to the subsequent combined elements. These variables and intermediate values can now also be processed in the wall reveal, air gap, and jamb areas and passed on to the timber-frame construction assignment. A typical use case is the "bottom air gap": This is specified in the default values for all windows. The first combined element also adopts this as an external variable. There, however, the variable can be overridden at the individual window in order to define a special air gap only for this window. Nothing needs to be changed in the setting for the "bottom air gap"; there the variable now also appears, which automatically adopts the value from the combined element. In order to use a variable or an intermediate value of the combined element, the variable or intermediate value must be defined as a variable in the default values of the structure. Thus, even an intermediate value must be defined as a variable in the default values. HRB editor: In formulas of opening settings and intermediate values of the HRB file, the variables and intermediate values of the opening are used. During assignment, the HRB interpreter takes exactly the values for that opening at each opening. This enables very precise control at each individual window. This is suitable, for example, for transferring information about belt winders or the type of lower connection for floor-to-ceiling windows (balcony, terrace, facade). To be able to use a variable or an intermediate value of the combined element, the variable or intermediate value must be defined as an external variable in the variables of the HRB file. Special possibilities arise here when using IFC Premium: through the assignments, the variables of the first combined element can be addressed directly. A specific value for, for example, "air below" can thus be controlled via IFC, so the requirement from the shop drawing stage can also be transferred into the HRB assignment. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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