====== Geometry Query Options ======
When **SteGetGeometry()** is called, it takes an **SSteGeometryOptions** pointer to a structure that will control what will be exported as well as how. There are numerous parameters, most of which are detailed below.

It's a good practice to use **SteInitGeometryOptions()** to initialize **SSteGeometryOptions** objects since there are no constructors in C. Its first parameter is an SSteEngine pointer. If NULL, it will use arbitrary default values. If a valid pointer is used, it will use value stored in the model file for some parameters. See the chart below.

^  Member Variable  ^  Default  ^  Purpose  ^
|  **m_eResolution**  |  Value saved in STE/SPM or HIGH  |Every SpeedTree model in version 8 or higher has four built-in resolutions: draft, low, medium, and high. The artist is in full control of the polygon counts for each.|
|  **m_eGroupType**  |  STE_GROUP_BY_GEOMETRY_TYPE  |Determines how the geometry will be organized: i) grouped by like geometry type, ii) grouped by like material, or iii) hierarchy. Grouping by geometry and material results in a flat hierarchy (all data is contained in nodes directly underneath the root noode).|
|  **m_nHierarchy**  |  0  |When m_eGroupType is set to STE_GROUP_BY_HIERARCHY, m_nHierarchy sets the level in the tree under which the tree will be split apart. For example, a level of 0 means the entire mesh in one group. A level of 1 means the trunks of the tree will each be in different groups with their children (in most cases of simple trees, this will be identical to level 0 since there is only one trunk). With a level of 2, the trunk will be in one group and then each major branch will be in a group with all of its children. More explanation [[http://docs8.speedtree.com/modeler/doku.php?id=expstaticmesh#group_by|here]], including a useful illustration.|
|  **m_uiSeed**  |  0  |Different seed values generate different models; 0 means to use the model as it was defined in Cinema.|
|  **m_fWindTimeInSecs**  |  0.0  |Drives the wind animation.|
|  **m_fGrowthFrame**  |  0.0  |Drives the growth animation. The number of frames is determined by the timeline in Cinema.|
|  **m_bUseUniquePositions**  |  false  |Export position values separately from compound vertex data; keeps position values from repeating on seams.|
|  **m_bExportBranchSpines**  \\   **m_bExport3dGeometry**  \\   **m_bExportBones**  \\   **m_bExportLeafRefs**  \\   **m_bBranchSeamBlending**  |  false  \\   true  \\   false  \\   false  \\   true  |Engine doesn't have to export everything at once. This is good way to streamline performance when only certain components are needed.|
|  **m_bComputeVelocities**  |  false  |Include velocity vectors in wind computations. Off by default because it doubles the wind computation time.|
|  **m_bTrianglesOnly**  |  false  |Convert all quads to triangles.|
|  **m_bPosSwapYZ**  \\   **m_bPosFlipX**  \\   **m_bPosFlipY**  \\   **m_bPosFlipZ**  \\   **m_fPosScalar**  \\   **m_bTextureFlipV**  |  false  \\   false  \\   false  \\   false  \\   1.0  \\   false  |Engine is right-handed / Z-up by default. Use these flags to automatically change the output coordinates as needed. Can also scale the model, modify UV coordinates.|
|  **m_fSeason**  |  Value saved in STE/SPM or 0.0  |Ranges from 0.0 to 1.0 and corresponds to the season slider in the Cinema interface.|
|  **m_bSeasonShowDroppedLeaves**  |  Value saved in STE/SPM or false  |Generate geometry for leaves that fall from the tree as the season changes.|
|  **m_bWindActive**  |  false  |When false, all expensive wind computation is bypassed.|
|  **m_fWindPrerollInSecs**  |  10.0  |Used to bypass the start-up of the wind algorithm as it reaches steady-state.|
|  **m_fWindStrength**  |  0.5  |0.0 to 1.0 scale. 0.0 is no wind, 1.0 is full wind. Corresponds to full range of wind speed indicator in the Cinema interface.|
|  **m_vWindDirection**  |  (1.0, 0.0, 0.0)  |Normalized wind vector.|
|  **m_bWindFast3dNoise**  |  false  |When enabled, wind compuation uses a faster but less smooth noise lookup technique. Speed can increase 30-50%.|
|  **m_sInstance**  |  (0.0, 0.0, 0.0)  |Used to offset the wind noise algorithm so that the same tree model placed in two separate positions animate with different wind.|
|  **m_pWindInternalState**  |  NULL  |Used to support random access of wind state, often for network rendering (advanced).|
|  **m_afWindInternalStateTransform**  |  Identity matrix  |Used to transform the wind direction to account for different coordinate systems.|
|  **m_bWindPointSource**  |  false  |Internal use.|
|  **m_vWindSourcePos**  |  (0.0, 0.0, 0.0)  |Internal use.|
|  **m_fWindCohesiveSync**  |  1.0  |Internal use.|
|  **m_bGrowthActive**  |  true  |If the loaded tree model is configured for growth, this flag will ensure that the model grows over time, driven by m_fTimeInSecs above.|