SoQuadMesh(3)

📦 version 3.1.3, in fedora 43, fedora 44

💖 SoQuadMesh(3) — Library Functions Manual 💖

okay bestie, sit down, hydrate, because this one is a banger. this is the manual page for SoQuadMesh, and it's giving big-node energy. it's long, so we're doing it in parts — this is part 1, and there's more coming, don't go anywhere. ✨

🌸 NAME 🌸

The SoQuadMesh class is used to render and optimize a quadrilateral mesh. yes, that's the whole job description, and she does it flawlessly. 👑

✨ SYNOPSIS ✨

first things first, you gotta let the compiler know she exists:

#include <Inventor/nodes/SoQuadMesh.h>

Inherits SoNonIndexedShape. the family tree goes deep, and we're about to show you every single ancestor, no cap. 🦋

💅 Public Member Functions

virtual SoType getTypeId (void) const
SoQuadMesh (void)
virtual void GLRender (SoGLRenderAction *action)
virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action)
virtual SbBool generateDefaultNormals (SoState *state, SoNormalBundle *nb)

🫶 Public Member Functions inherited from SoVertexShape

virtual void notify (SoNotList *nl)
virtual void write (SoWriteAction *action)

🌈 Public Member Functions inherited from SoShape

virtual SbBool affectsState (void) const
virtual void getBoundingBox (SoGetBoundingBoxAction *action)
virtual void rayPick (SoRayPickAction *action)
virtual void callback (SoCallbackAction *action)
const SoBoundingBoxCache * getBoundingBoxCache (void) const

🎀 Public Member Functions inherited from SoNode

void setOverride (const SbBool state)
SbBool isOverride (void) const
void setNodeType (const NodeType type)
NodeType getNodeType (void) const
virtual SoNode * copy (SbBool copyconnections=FALSE) const
virtual void doAction (SoAction *action)
virtual void GLRenderBelowPath (SoGLRenderAction *action)
virtual void GLRenderInPath (SoGLRenderAction *action)
virtual void GLRenderOffPath (SoGLRenderAction *action)
virtual void getMatrix (SoGetMatrixAction *action)
virtual void handleEvent (SoHandleEventAction *action)
virtual void pick (SoPickAction *action)
virtual void search (SoSearchAction *action)
virtual void audioRender (SoAudioRenderAction *action)
virtual void grabEventsSetup (void)
virtual void grabEventsCleanup (void)
virtual void startNotify (void)
uint32_t getNodeId (void) const
virtual SoChildList * getChildren (void) const
virtual void writeInstance (SoOutput *out)
virtual SoNode * addToCopyDict (void) const
virtual void copyContents (const SoFieldContainer *from, SbBool copyconnections)
virtual SoFieldContainer * copyThroughConnection (void) const

🦋 Public Member Functions inherited from SoFieldContainer

void setToDefaults (void)
SbBool hasDefaultValues (void) const
SbBool fieldsAreEqual (const SoFieldContainer *container) const
void copyFieldValues (const SoFieldContainer *container, SbBool copyconnections=FALSE)
SbBool set (const char *const fielddata)
void get (SbString &fielddata)
virtual int getFields (SoFieldList &l) const
virtual int getAllFields (SoFieldList &l) const
virtual SoField * getField (const SbName &name) const
virtual SoField * getEventIn (const SbName &name) const
virtual SoField * getEventOut (const SbName &name) const
SbBool getFieldName (const SoField *const field, SbName &name) const
SbBool enableNotify (const SbBool flag)
SbBool isNotifyEnabled (void) const
SbBool set (const char *fielddata, SoInput *input)
void get (SbString &fielddata, SoOutput *out)
virtual SbBool validateNewFieldValue (SoField *field, void *newval)
virtual void addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
SbBool getIsBuiltIn (void) const
virtual void getFieldsMemorySize (size_t &managed, size_t &unmanaged) const
void setUserData (void *userdata) const
void * getUserData (void) const

💜 Public Member Functions inherited from SoBase

void ref (void) const
void unref (void) const
void unrefNoDelete (void) const
int32_t getRefCount (void) const
void touch (void)
SbBool isOfType (SoType type) const
virtual SbName getName (void) const
virtual void setName (const SbName &newname)
void addAuditor (void *const auditor, const SoNotRec::Type type)
void removeAuditor (void *const auditor, const SoNotRec::Type type)
const SoAuditorList & getAuditors (void) const
SbBool shouldWrite (void)
void assertAlive (void) const

⭐ Static Public Member Functions

static SoType getClassTypeId (void)
static void initClass (void)

🍓 Static Public Member Functions inherited from SoNonIndexedShape

static SoType getClassTypeId (void)
static void initClass (void)

🧚 Static Public Member Functions inherited from SoVertexShape

static SoType getClassTypeId (void)
static void initClass (void)

🔥 Static Public Member Functions inherited from SoShape

static SoType getClassTypeId (void)
static void initClass (void)
static void getScreenSize (SoState *const state, const SbBox3f &boundingbox, SbVec2s &rectsize)
static float getDecimatedComplexity (SoState *state, float complexity)

🌸 Static Public Member Functions inherited from SoNode

static uint32_t getCompatibilityTypes (const SoType &nodetype)
static SoType getClassTypeId (void)
static SoNode * getByName (const SbName &name)
static int getByName (const SbName &name, SoNodeList &l)
static void initClass (void)
static void initClasses (void)
static uint32_t getNextNodeId (void)
static int getActionMethodIndex (const SoType type)
static void getBoundingBoxS (SoAction *action, SoNode *node)
static void GLRenderS (SoAction *action, SoNode *node)
static void callbackS (SoAction *action, SoNode *node)
static void getMatrixS (SoAction *action, SoNode *node)
static void handleEventS (SoAction *action, SoNode *node)
static void pickS (SoAction *action, SoNode *node)
static void rayPickS (SoAction *action, SoNode *node)
static void searchS (SoAction *action, SoNode *node)
static void writeS (SoAction *action, SoNode *node)
static void audioRenderS (SoAction *action, SoNode *node)
static void getPrimitiveCountS (SoAction *action, SoNode *node)

🌈 Static Public Member Functions inherited from SoFieldContainer

static void initClass (void)
static SoType getClassTypeId (void)
static void cleanupClass (void)
static void initCopyDict (void)
static void addCopy (const SoFieldContainer *orig, const SoFieldContainer *copy)
static SoFieldContainer * checkCopy (const SoFieldContainer *orig)
static SoFieldContainer * findCopy (const SoFieldContainer *orig, const SbBool copyconnections)
static void copyDone (void)

💖 Static Public Member Functions inherited from SoBase

static void initClass (void)
static SoType getClassTypeId (void)
static void addName (SoBase *const base, const char *const name)
static void removeName (SoBase *const base, const char *const name)
static void incrementCurrentWriteCounter (void)
static void decrementCurrentWriteCounter (void)
static SoBase * getNamedBase (const SbName &name, SoType type)
static int getNamedBases (const SbName &name, SoBaseList &baselist, SoType type)
static SbBool read (SoInput *input, SoBase *&base, SoType expectedtype)
static void setInstancePrefix (const SbString &c)
static void setTraceRefs (SbBool trace)
static SbBool getTraceRefs (void)
static SbBool connectRoute (SoInput *input, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)
static SbBool readRoute (SoInput *input)

👑 Public Attributes

these are the fields that make her her:

SoSFInt32 verticesPerColumn
SoSFInt32 verticesPerRow

🫶 Public Attributes inherited from SoNonIndexedShape

SoSFInt32 startIndex

🦋 Public Attributes inherited from SoVertexShape

SoSFNode vertexProperty

💅 Protected Member Functions

the ones you only get to touch if you're in the family (i.e. subclassing, iykyk):

virtual const SoFieldData * getFieldData (void) const
virtual ~SoQuadMesh ()
virtual void generatePrimitives (SoAction *action)
virtual void computeBBox (SoAction *action, SbBox3f &box, SbVec3f &center)
virtual SbBool generateDefaultNormals (SoState *, SoNormalCache *)

🌸 Protected Member Functions inherited from SoNonIndexedShape

SoNonIndexedShape (void)
virtual ~SoNonIndexedShape ()
void computeCoordBBox (SoAction *action, int numVertices, SbBox3f &box, SbVec3f &center)
void fixNumVerticesPointers (SoState *state, const int32_t *&start, const int32_t *&end, int32_t *dummyarray) const

🎀 Protected Member Functions inherited from SoVertexShape

SoVertexShape (void)
virtual ~SoVertexShape ()
virtual SbBool shouldGLRender (SoGLRenderAction *action)
void setNormalCache (SoState *const state, const int num, const SbVec3f *normals)
SoNormalCache * getNormalCache (void) const
SoNormalCache * generateAndReadLockNormalCache (SoState *const state)
void getVertexData (SoState *state, const SoCoordinateElement *&coords, const SbVec3f *&normals, const SbBool neednormals)
void readLockNormalCache (void)
void readUnlockNormalCache (void)

🫶 bestie, that was just the SYNOPSIS and the whole inherited-functions glow-up. the juicy parts — the actual SoQuadMesh behaviour, the fields in action, all the lore — are still coming. part 2 is loading… ✨

🛡️ Protected Member Functions inherited from SoShape

okay so these are the ones the class keeps lowkey to itself (protected, bestie — for the internals and subclasses, not for you to just vibe with):

SoShape (void)
virtual ~SoShape ()
float getComplexityValue (SoAction *action)
void beginSolidShape (SoGLRenderAction *action)
void endSolidShape (SoGLRenderAction *action)
void GLRenderBoundingBox (SoGLRenderAction *action)
SbBool shouldPrimitiveCount (SoGetPrimitiveCountAction *action)
SbBool shouldRayPick (SoRayPickAction *const action)
void computeObjectSpaceRay (SoRayPickAction *const action)
void computeObjectSpaceRay (SoRayPickAction *const action, const SbMatrix &matrix)
virtual SoDetail * createTriangleDetail (SoRayPickAction *action, const SoPrimitiveVertex *v1, const SoPrimitiveVertex *v2, const SoPrimitiveVertex *v3, SoPickedPoint *pp)
virtual SoDetail * createLineSegmentDetail (SoRayPickAction *action, const SoPrimitiveVertex *v1, const SoPrimitiveVertex *v2, SoPickedPoint *pp)
virtual SoDetail * createPointDetail (SoRayPickAction *action, const SoPrimitiveVertex *v, SoPickedPoint *pp)
void invokeTriangleCallbacks (SoAction *const action, const SoPrimitiveVertex *const v1, const SoPrimitiveVertex *const v2, const SoPrimitiveVertex *const v3)
void invokeLineSegmentCallbacks (SoAction *const action, const SoPrimitiveVertex *const v1, const SoPrimitiveVertex *const v2)
void invokePointCallbacks (SoAction *const action, const SoPrimitiveVertex *const v)
void beginShape (SoAction *const action, const TriangleShape shapetype, SoDetail *const detail=NULL)
void shapeVertex (const SoPrimitiveVertex *const v)
void endShape (void)
void generateVertex (SoPrimitiveVertex *const pv, const SbVec3f &point, const SbBool useTexFunc, const SoTextureCoordinateElement *const tce, const float s, const float t, const SbVec3f &normal)
void generateVertex (SoPrimitiveVertex *const pv, const SbVec3f &point, const SbBool useTexFunc, const SoTextureCoordinateElement *const tce, const float s, const float t, const float r, const SbVec3f &normal)
SbBool startVertexArray (SoGLRenderAction *action, const SoCoordinateElement *coords, const SbVec3f *pervertexnormals, const SbBool texpervertex, const SbBool colorpervertex)
void finishVertexArray (SoGLRenderAction *action, const SbBool vbo, const SbBool normpervertex, const SbBool texpervertex, const SbBool colorpervertex)

🛡️ Protected Member Functions inherited from SoNode

SoNode (void)
virtual ~SoNode ()
virtual SbBool readInstance (SoInput *in, unsigned short flags)

🛡️ Protected Member Functions inherited from SoFieldContainer

SoFieldContainer (void)
virtual ~SoFieldContainer ()

🛡️ Protected Member Functions inherited from SoBase

SoBase (void)
virtual ~SoBase ()
virtual void destroy (void)
SbBool hasMultipleWriteRefs (void) const
SbBool writeHeader (SoOutput *out, SbBool isgroup, SbBool isengine) const
void writeFooter (SoOutput *out) const
virtual const char * getFileFormatName (void) const

🌟 Static Protected Member Functions

static const SoFieldData ** getFieldDataPtr (void)

🌟 Static Protected Member Functions inherited from SoNonIndexedShape

static const SoFieldData ** getFieldDataPtr (void)

🌟 Static Protected Member Functions inherited from SoVertexShape

static const SoFieldData ** getFieldDataPtr (void)

🌟 Static Protected Member Functions inherited from SoShape

static const SoFieldData ** getFieldDataPtr (void)

🌟 Static Protected Member Functions inherited from SoNode

static const SoFieldData ** getFieldDataPtr (void)
static void setNextActionMethodIndex (int index)
static int getNextActionMethodIndex (void)
static void incNextActionMethodIndex (void)
static void setCompatibilityTypes (const SoType &nodetype, const uint32_t bitmask)

🌟 Static Protected Member Functions inherited from SoBase

static uint32_t getCurrentWriteCounter (void)
static void staticDataLock (void)
static void staticDataUnlock (void)

💫 Additional Inherited Members

💫 Public Types inherited from SoShape

enum TriangleShape { TRIANGLE_STRIP, TRIANGLE_FAN, TRIANGLES, POLYGON, QUADS, QUAD_STRIP, POINTS, LINES, LINE_STRIP }

💫 Public Types inherited from SoNode

enum NodeType { INVENTOR = 0x0000, VRML1 = 0x0001, VRML2 = 0x0002, INVENTOR_1 = 0x0004, INVENTOR_2_0 = 0x0008, INVENTOR_2_1 = 0x0010, INVENTOR_2_5 = 0x0020, INVENTOR_2_6 = 0x0040, COIN_1_0 = 0x0080, COIN_2_0 = 0x0100, EXTENSION = 0x0200, COIN_2_2 = 0x0400, COIN_2_3 = 0x0800, COIN_2_4 = 0x1000, INVENTOR_5_0 = 0x2000, COIN_2_5 = 0x4000, COIN_3_0 = 0x8000, INVENTOR_6_0 = 0x10000 }

💫 Protected Types inherited from SoBase

enum BaseFlags { IS_ENGINE = 0x01, IS_GROUP = 0x02 }

💫 Protected Attributes inherited from SoNode

uint32_t uniqueId

💫 Protected Attributes inherited from SoFieldContainer

SbBool isBuiltIn

💫 Static Protected Attributes inherited from SoNode

static uint32_t nextUniqueId = 1
static int nextActionMethodIndex = 0

📖 Detailed Description

The SoQuadMesh class is used to render and optimize a quadrilateral mesh. 💅✨

This node uses the coordinates in order, either from the state or from the SoQuadMesh::vertexProperty node, to construct a quadrilateral mesh.

The quads are generated in row major order, using the two fields SoQuadMesh::verticesPerColumn and SoQuadMesh::verticesPerRow to specify the mesh. E.g. if SoQuadMesh::verticesPerColumn is 3 and SoQuadMesh::verticesPerRow is 2, two quads will be generated with the first one using (in order) coordinates 0, 1, 3 and 2, the second one using coordinates 2, 3, 5 and 4 (you get three rows of vertices; the first row uses vertices 0 and 1, the second row 2 and 3, and the third row 4 and 5). 🧮✨

Here's a quick and simple usage example code snippet:

// Vertices for the Quad mesh.
static float vertices[25][3] = {
  // Row 1
  {-11, 0, 1}, {0, 11, 1}, {11, 0, 1}, {0, -11, 1}, {-11, 0, 1},
  // Row 2
  {-9, 0, 1}, {0, 9, 1}, {9, 0, 1}, {0, -9, 1}, {-9, 0, 1},
  // Row 3
  {-9, 0, -1}, {0, 9, -1}, {9, 0, -1}, {0, -9, -1}, {-9, 0, -1},
  // Row 4
  {-11, 0, -1}, {0, 11, -1}, {11, 0, -1}, {0, -11, -1}, {-11, 0, -1},
  // Row 5
  {-11, 0, 1}, {0, 11, 1}, {11, 0, 1}, {0, -11, 1}, {-11, 0, 1}
};

// This function generate an object by using the SoQuadMesh node
// Return:
//  SoSeparator *
static SoSeparator *
quadMesh(void)
{
  SoSeparator * qm = new SoSeparator;

  // Define coordinates
  SoCoordinate3 * coords = new SoCoordinate3;
  coords->point.setValues(0, 30, vertices);
  qm->addChild(coords);

  // QuadMesh
  SoQuadMesh * mesh = new SoQuadMesh;
  mesh->verticesPerRow = 5;
  mesh->verticesPerColumn = 5;
  qm->addChild(mesh);

  return qm;
}

The quadmesh geometry resulting from this code looks like this: 👀

Here is another example, this time making a 2x2 grid, with a texture:

#Inventor V2.1 ascii

Separator {
  Complexity { textureQuality 0.01 }
  Texture2 {
    image 2 2 4 0xff0000ff 0x00ff00ff 0xffff00ff 0xff00ffff
  }
  Coordinate3 {
    point [
      0 2 0,
      1 2 0,
      2 2 0,
      0 1 0,
      1 1 0,
      2 1 0,
      0 0 0,
      1 0 0,
      2 0 0
    ]
  }
  QuadMesh {
    verticesPerRow 3
    verticesPerColumn 3
  }
}

For SoQuadMesh, normals and materials can be bound PER_PART (per row), PER_FACE, PER_VERTEX and OVERALL. The default material binding is OVERALL. The default normal binding is PER_VERTEX. 🔥

A note about SoQuadMesh shading: the quads in the mesh are just passed on to OpenGL's GL_QUAD primitive rendering. Under certain circumstances, this can lead to artifacts in how your meshes are shaded. This is an inherent problem with drawing quads in meshes. 😭

There is a work-around solution for the above mentioned problem that can be applied with Coin: by setting the global environment variable COIN_QUADMESH_PRECISE_LIGHTING to "1", the quads will be broken up in triangles before rendered, and shading will likely look much better. Be aware that this technique causes rendering of the SoQuadMesh to slow down by an approximate factor of 6. 🐌💀

The "precise lighting" technique is currently limited to work only when SoQuadMesh rendering is parameterized with 3D coordinates, a materialbinding that is not per vertex, and if texture mapping is done is must be without using any of the SoTextureCoordinateFunction subclass nodes.

FILE FORMAT/DEFAULTS:

QuadMesh {
    vertexProperty NULL
    startIndex 0
    verticesPerColumn 1
    verticesPerRow 1
}

👀 See also

SoTriangleStripSet SoIndexedTriangleStripSet

🔧 Constructor & Destructor Documentation

🔧 SoQuadMesh::SoQuadMesh (void )

Constructor. 🎀

🔧 SoQuadMesh::~SoQuadMesh () [protected], [virtual]

Destructor. 💖

💖 Member Function Documentation 💖

✨ `SoType SoQuadMesh::getTypeId (void ) const [virtual]` ✨

Okay bestie, this one returns the type identification of an object derived from a class inheriting SoBase. It's literally the glow-up for run-time type checking and "downward" casting. 👑

Usage example:

void foo(SoNode * node)
{
  if (node->getTypeId() == SoFile::getClassTypeId()) {
    SoFile * filenode = (SoFile *)node;  // safe downward cast, knows the type
  }
}

For application programmers wanting to extend the library with new nodes, engines, nodekits, draggers or others: this method needs to be overridden in all subclasses. This is typically done as part of setting up the full type system for extension classes, which is usually accomplished by using the pre-defined macros available through for instance Inventor/nodes/SoSubNode.h (SO_NODE_INIT_CLASS and SO_NODE_CONSTRUCTOR for node classes), Inventor/engines/SoSubEngine.h (for engine classes) and so on.

For more information on writing Coin extensions, see the class documentation of the toplevel superclasses for the various class groups.

Reimplemented from SoNonIndexedShape.

🌸 `const SoFieldData * SoQuadMesh::getFieldData (void ) const [protected], [virtual]` 🌸

Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL.

Reimplemented from SoNonIndexedShape.

🦋 `void SoQuadMesh::GLRender (SoGLRenderAction * action) [virtual]` 🦋

Action method for the SoGLRenderAction.

This is called during rendering traversals. Nodes influencing the rendering state in any way or who wants to throw geometry primitives at OpenGL overrides this method.

Reimplemented from SoShape.

🎀 `void SoQuadMesh::getPrimitiveCount (SoGetPrimitiveCountAction * action) [virtual]` 🎀

Action method for the SoGetPrimitiveCountAction.

Calculates the number of triangle, line segment and point primitives for the node and adds these to the counters of the action.

Nodes influencing how geometry nodes calculates their primitive count also overrides this method to change the relevant state variables.

Reimplemented from SoShape.

💅 `SbBool SoQuadMesh::generateDefaultNormals (SoState * state, SoNormalBundle * bundle) [virtual]` 💅

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

Subclasses should override this method to generate default normals using the SoNormalBundle class. TRUE should be returned if normals were generated, FALSE otherwise.

Default method returns FALSE.

This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

Reimplemented from SoVertexShape.

🌈 `void SoQuadMesh::generatePrimitives (SoAction * action) [protected], [virtual]` 🌈

The method implements action behavior for shape nodes for SoCallbackAction. It is invoked from SoShape::callback(). (Subclasses should not override SoNode::callback().)

The subclass implementations uses the convenience methods SoShape::beginShape(), SoShape::shapeVertex(), and SoShape::endShape(), with SoDetail instances, to pass the primitives making up the shape back to the caller.

Implements SoShape.

⭐ `void SoQuadMesh::computeBBox (SoAction * action, SbBox3f & box, SbVec3f & center) [protected], [virtual]` ⭐

Implemented by SoShape subclasses to let the SoShape superclass know the exact size and weighted center point of the shape's bounding box.

The bounding box and center point should be calculated and returned in the local coordinate system.

The method implements action behavior for shape nodes for SoGetBoundingBoxAction. It is invoked from SoShape::getBoundingBox(). (Subclasses should not override SoNode::getBoundingBox().)

The box parameter sent in is guaranteed to be an empty box, while center is undefined upon function entry.