ezEngine  Release 25.03
ezGeometry Class Reference

Provides functions to generate standard geometric shapes, such as boxes, spheres, cylinders, etc. More...

#include <Geometry.h>

Classes

struct  GeoOptions
 Options shared among all geometry creation functions. More...
 
struct  Line
 A line only references two vertices. More...
 
struct  Polygon
 Each polygon has a face normal and a set of indices, which vertices it references. More...
 
struct  Vertex
 The data that is stored per vertex. More...
 

Public Member Functions

ezDeque< Vertex > & GetVertices ()
 Returns the entire vertex data.
 
ezDeque< Polygon > & GetPolygons ()
 Returns the entire polygon data.
 
ezDeque< Line > & GetLines ()
 Returns the entire line data.
 
const ezDeque< Vertex > & GetVertices () const
 Returns the entire vertex data.
 
const ezDeque< Polygon > & GetPolygons () const
 Returns the entire polygon data.
 
const ezDeque< Line > & GetLines () const
 Returns the entire line data.
 
void Clear ()
 Clears all data.
 
ezUInt32 AddVertex (const ezVec3 &vPos, const ezVec3 &vNormal, const ezVec2 &vTexCoord=ezVec2(0.0f), const ezColor &color=ezColor::White, const ezVec4U16 &vBoneIndices=ezVec4U16::MakeZero(), const ezColorLinearUB &boneWeights=ezColorLinearUB(255, 0, 0, 0))
 Adds a vertex, returns the index to the added vertex.
 
ezUInt32 AddVertex (const ezMat4 &mTransform, const ezVec3 &vPos, const ezVec3 &vNormal, const ezVec2 &vTexCoord=ezVec2(0.0f), const ezColor &color=ezColor::White, const ezVec4U16 &vBoneIndices=ezVec4U16::MakeZero(), const ezColorLinearUB &boneWeights=ezColorLinearUB(255, 0, 0, 0))
 Overload that transforms position and normal with the given matrix.
 
ezUInt32 AddVertex (const GeoOptions &options, const ezVec3 &vPos, const ezVec3 &vNormal, const ezVec2 &vTexCoord=ezVec2(0.0f))
 Overload that uses the options for color and to transform position and normal and uses a single bone.
 
ezUInt32 AddVertex (const ezMat4 &mTransform, const GeoOptions &options, const ezVec3 &vPos, const ezVec3 &vNormal, const ezVec2 &vTexCoord=ezVec2(0.0f))
 Overload that uses the options for color and a single bone and transforms position and normal by a separately provided matrix.
 
void AddPolygon (const ezArrayPtr< ezUInt32 > &vertices, bool bFlipWinding)
 Adds a polygon that consists of all the referenced vertices. No face normal is computed at this point.
 
void AddLine (ezUInt32 uiStartVertex, ezUInt32 uiEndVertex)
 Adds a line with the given start and end vertex index.
 
void TriangulatePolygons (ezUInt32 uiMaxVerticesInPolygon=3)
 Triangulates all polygons that have more than uiMaxVerticesInPolygon vertices. More...
 
void ComputeFaceNormals ()
 Computes normals for all polygons from the current vertex positions. Call this when you do not intend to make further modifications.
 
void ComputeSmoothVertexNormals ()
 Computes smooth (averaged) normals for each vertex. Requires that face normals are computed. More...
 
void ComputeTangents ()
 Computes tangents. This function can increase or reduce vertex count. More...
 
void ValidateTangents (float fEpsilon=0.01f)
 Checks whether present tangents are meaningful and resets them, if necessary. More...
 
ezUInt32 CalculateTriangleCount () const
 Returns the number of triangles that the polygons are made up of.
 
void SetAllVertexBoneIndices (const ezVec4U16 &vBoneIndices, ezUInt32 uiFirstVertex=0)
 Changes the bone indices for all vertices (starting at vertex uiFirstVertex).
 
void SetAllVertexColor (const ezColor &color, ezUInt32 uiFirstVertex=0)
 Changes the color for all vertices (starting at vertex uiFirstVertex).
 
void SetAllVertexTexCoord (const ezVec2 &vTexCoord, ezUInt32 uiFirstVertex=0)
 Changes the texture coordinates for all vertices (starting at vertex uiFirstVertex).
 
void Transform (const ezMat4 &mTransform, bool bTransformPolyNormals)
 Transforms all vertices by the given transform. More...
 
void Merge (const ezGeometry &other)
 Merges the given mesh into this one. Use this to composite multiple shapes into one.
 
void AddRect (const ezVec2 &vSize, ezUInt32 uiTesselationX=1, ezUInt32 uiTesselationY=1, const GeoOptions &options=GeoOptions())
 Adds a rectangle shape, with the front pointing into the main axis direction. More...
 
void AddBox (const ezVec3 &vFullExtents, bool bExtraVerticesForTexturing, const GeoOptions &options=GeoOptions())
 Adds a box. If bExtraVerticesForTexturing is false, 8 shared vertices are added. If bExtraVerticesForTexturing is true, 24 separate vertices with UV coordinates are added.
 
void AddLineBox (const ezVec3 &vSize, const GeoOptions &options=GeoOptions())
 Adds box out of lines (8 vertices).
 
void AddLineBoxCorners (const ezVec3 &vSize, float fCornerFraction, const GeoOptions &options=GeoOptions())
 Adds the 8 corners of a box as lines. More...
 
void AddPyramid (float fBaseSize, float fHeight, bool bCap, const GeoOptions &options=GeoOptions())
 Adds a pyramid. This is different to a low-res cone in that the corners are placed differently (like on a box). More...
 
void AddGeodesicSphere (float fRadius, ezUInt8 uiSubDivisions, const GeoOptions &options=GeoOptions())
 Adds a geodesic sphere at the origin. More...
 
void AddCylinder (float fRadiusTop, float fRadiusBottom, float fPositiveLength, float fNegativeLength, bool bCapTop, bool bCapBottom, ezUInt16 uiSegments, const GeoOptions &options=GeoOptions(), ezAngle fraction=ezAngle::MakeFromDegree(360.0f))
 Adds a cylinder revolving around the main axis (see GeoOptions). More...
 
void AddCylinderOnePiece (float fRadiusTop, float fRadiusBottom, float fPositiveLength, float fNegativeLength, ezUInt16 uiSegments, const GeoOptions &options=GeoOptions())
 Same as AddCylinder(), but always adds caps and does not generate separate vertices for the caps. More...
 
void AddCone (float fRadius, float fHeight, bool bCap, ezUInt16 uiSegments, const GeoOptions &options=GeoOptions())
 Adds a cone with the origin at the center of the bottom and the tip pointing into the direction of the main axis (see GeoOptions). More...
 
void AddStackedSphere (float fRadius, ezUInt16 uiSegments, ezUInt16 uiStacks, const GeoOptions &options=GeoOptions())
 Adds a sphere consisting of a number of stacks along the main axis (see GeoOptions) with a fixed tessellation. More...
 
void AddHalfSphere (float fRadius, ezUInt16 uiSegments, ezUInt16 uiStacks, bool bCap, const GeoOptions &options=GeoOptions())
 Adds half a stacked sphere with the half being in the direction of the main axis (see GeoOptions). More...
 
void AddCapsule (float fRadius, float fHeight, ezUInt16 uiSegments, ezUInt16 uiStacks, const GeoOptions &options=GeoOptions())
 Adds a capsule, revolving around the main axis (see GeoOptions). More...
 
void AddTorus (float fInnerRadius, float fOuterRadius, ezUInt16 uiSegments, ezUInt16 uiSegmentDetail, bool bExtraVerticesForTexturing, const GeoOptions &options=GeoOptions())
 Adds a full torus with the ring revolving around the main axis (see GeoOptions). More...
 
void AddTexturedRamp (const ezVec3 &vSize, const GeoOptions &options=GeoOptions())
 Adds a ramp that has UV coordinates set.
 
void AddStairs (const ezVec3 &vSize, ezUInt32 uiNumSteps, ezAngle curvature, bool bSmoothSloped, const GeoOptions &options=GeoOptions())
 Generates a straight stair mesh along the X axis. The number of steps determines the step height and depth.
 
void AddArch (const ezVec3 &vSize, ezUInt32 uiNumSegments, float fThickness, ezAngle angle, bool bMakeSteps, bool bSmoothBottom, bool bSmoothTop, bool bCapTopAndBottom, const GeoOptions &options=GeoOptions())
 Creates and arch, pipe or spiral stairs within the defined volume (size) curving around the main axis. More...
 

Detailed Description

Provides functions to generate standard geometric shapes, such as boxes, spheres, cylinders, etc.

This class provides simple functions to create frequently used basic shapes. It allows to transform the shapes, merge them into a single mesh, compute normals, etc. It is meant for debug and editor geometry (gizmos, etc.). Vertices can have position, normal, color and 'shape index'.

Member Function Documentation

◆ AddArch()

void ezGeometry::AddArch ( const ezVec3 vSize,
ezUInt32  uiNumSegments,
float  fThickness,
ezAngle  angle,
bool  bMakeSteps,
bool  bSmoothBottom,
bool  bSmoothTop,
bool  bCapTopAndBottom,
const GeoOptions options = GeoOptions() 
)

Creates and arch, pipe or spiral stairs within the defined volume (size) curving around the main axis.

Parameters
uiNumSegmentsThe number of segments of the arch or pipe, or the number of steps in spiral stairs.
fThicknessThe wall thickness of the pipe, or the width of steps.
angleHow far to curl around the main axis. Values between -360 degree and +360 degree are possible. 0 degree is treated like 360 degree.
bMakeStepsIf true, segments are only thin and are offset in position from the previous one.
bSmoothBottom,bSmoothTopIf true and bMakeSteps as well, the segments will have a step, but connect smoothly, like in a spiral.
bCapTopAndBottomIf false, the top and bottom geometry is skipped. Can be used to reduce detail in pipe geometry that connects with something else anyway.

◆ AddCapsule()

void ezGeometry::AddCapsule ( float  fRadius,
float  fHeight,
ezUInt16  uiSegments,
ezUInt16  uiStacks,
const GeoOptions options = GeoOptions() 
)

Adds a capsule, revolving around the main axis (see GeoOptions).

The origin is at the center of the capsule. Radius and height are added to get the total height of the capsule. uiSegments is the detail around the up axis, must be at least 3. uiStacks is the detail of the rounded top and bottom, must be at least 1.

◆ AddCone()

void ezGeometry::AddCone ( float  fRadius,
float  fHeight,
bool  bCap,
ezUInt16  uiSegments,
const GeoOptions options = GeoOptions() 
)

Adds a cone with the origin at the center of the bottom and the tip pointing into the direction of the main axis (see GeoOptions).

uiSegments is the detail around the up axis, must be at least 3.

◆ AddCylinder()

void ezGeometry::AddCylinder ( float  fRadiusTop,
float  fRadiusBottom,
float  fPositiveLength,
float  fNegativeLength,
bool  bCapTop,
bool  bCapBottom,
ezUInt16  uiSegments,
const GeoOptions options = GeoOptions(),
ezAngle  fraction = ezAngle::MakeFromDegree(360.0f) 
)

Adds a cylinder revolving around the main axis (see GeoOptions).

If fPositiveLength == fNegativeLength, the origin is at the center. If fNegativeLength is zero, the origin is at the bottom and so on.

uiSegments is the detail around the up axis, must be at least 3. The top or bottom caps can be removed using bCapTop and bCapBottom. When fraction is set to any value below 360 degree, a pie / PacMan-shaped cylinder is created.

◆ AddCylinderOnePiece()

void ezGeometry::AddCylinderOnePiece ( float  fRadiusTop,
float  fRadiusBottom,
float  fPositiveLength,
float  fNegativeLength,
ezUInt16  uiSegments,
const GeoOptions options = GeoOptions() 
)

Same as AddCylinder(), but always adds caps and does not generate separate vertices for the caps.

This is a more compact representation, but does not allow as good texturing.

◆ AddGeodesicSphere()

void ezGeometry::AddGeodesicSphere ( float  fRadius,
ezUInt8  uiSubDivisions,
const GeoOptions options = GeoOptions() 
)

Adds a geodesic sphere at the origin.

When uiSubDivisions is zero, the sphere will have 20 triangles.
For each subdivision step the number of triangles quadruples.
0 = 20 triangles, 12 vertices
1 = 80 triangles, 42 vertices
2 = 320 triangles, 162 vertices
3 = 1280 triangles, 642 vertices
4 = 5120 triangles, 2562 vertices
...

◆ AddHalfSphere()

void ezGeometry::AddHalfSphere ( float  fRadius,
ezUInt16  uiSegments,
ezUInt16  uiStacks,
bool  bCap,
const GeoOptions options = GeoOptions() 
)

Adds half a stacked sphere with the half being in the direction of the main axis (see GeoOptions).

The origin is at the 'full sphere center', ie. at the center of the cap. uiSegments is the detail around the up axis, must be at least 3. uiStacks is the detail of the rounded top and bottom, must be at least 1.

◆ AddLineBoxCorners()

void ezGeometry::AddLineBoxCorners ( const ezVec3 vSize,
float  fCornerFraction,
const GeoOptions options = GeoOptions() 
)

Adds the 8 corners of a box as lines.

fCornerFraction must be between 1.0 and 0.0, with 1 making it a completely closed box and 0 no lines at all.

◆ AddPyramid()

void ezGeometry::AddPyramid ( float  fBaseSize,
float  fHeight,
bool  bCap,
const GeoOptions options = GeoOptions() 
)

Adds a pyramid. This is different to a low-res cone in that the corners are placed differently (like on a box).

The origin is at the center of the base quad and the tip is in the direction of the main axis (see GeoOptions).

◆ AddRect()

void ezGeometry::AddRect ( const ezVec2 vSize,
ezUInt32  uiTesselationX = 1,
ezUInt32  uiTesselationY = 1,
const GeoOptions options = GeoOptions() 
)

Adds a rectangle shape, with the front pointing into the main axis direction.

It is centered at the origin, extending half size.x and half size.y into direction +X, -X, +Y and -Y. Optionally tessellates the rectangle for more detail.

◆ AddStackedSphere()

void ezGeometry::AddStackedSphere ( float  fRadius,
ezUInt16  uiSegments,
ezUInt16  uiStacks,
const GeoOptions options = GeoOptions() 
)

Adds a sphere consisting of a number of stacks along the main axis (see GeoOptions) with a fixed tessellation.

uiSegments is the detail around the up axis, must be at least 3. uiStacks is the detail along the up axis, must be at least 2.

◆ AddTorus()

void ezGeometry::AddTorus ( float  fInnerRadius,
float  fOuterRadius,
ezUInt16  uiSegments,
ezUInt16  uiSegmentDetail,
bool  bExtraVerticesForTexturing,
const GeoOptions options = GeoOptions() 
)

Adds a full torus with the ring revolving around the main axis (see GeoOptions).

The origin is at the center of the torus.

Parameters
fInnerRadiusis the radius from the center to where the torus ring starts.
fOuterRadiusis the radius to where the torus ring stops.
uiSegmentsis the detail around the main axis.
uiSegmentDetailis the number of segments around the torus ring (ie. the cylinder detail)
bExtraVerticesForTexturingspecifies whether the torus should be one closed piece or have additional vertices at the seams, such that texturing works better.

◆ ComputeSmoothVertexNormals()

void ezGeometry::ComputeSmoothVertexNormals ( )

Computes smooth (averaged) normals for each vertex. Requires that face normals are computed.

This only yields smooth normals for vertices that are shared among multiple polygons, otherwise a vertex will have the same normal as the one face that it is used in.

◆ ComputeTangents()

void ezGeometry::ComputeTangents ( )

Computes tangents. This function can increase or reduce vertex count.

The tangent generation is done by Morten S. Mikkelsen's tangent space generation code.

◆ Transform()

void ezGeometry::Transform ( const ezMat4 mTransform,
bool  bTransformPolyNormals 
)

Transforms all vertices by the given transform.

When bTransformPolyNormals is true, the polygon normals are transformed, as well. Set this to false when face normals are going to be computed later anyway.

◆ TriangulatePolygons()

void ezGeometry::TriangulatePolygons ( ezUInt32  uiMaxVerticesInPolygon = 3)

Triangulates all polygons that have more than uiMaxVerticesInPolygon vertices.

Set uiMaxVerticesInPolygon to 4, if you want to keep quads unchanged.

◆ ValidateTangents()

void ezGeometry::ValidateTangents ( float  fEpsilon = 0.01f)

Checks whether present tangents are meaningful and resets them, if necessary.

Checks if the tangents are approximately orthogonal to the vertex normal and of unit length. If this is not the case the respective tangent will be zeroed. The caller can provide a comparison epsilon.


The documentation for this class was generated from the following files: