SoCalculator(3)

📦 version 2.5.0, in fedora 43, fedora 44

okay so bestie, hydrate, sit down, and let's talk about SoCalculator(3) 💖 that's the page name right there in the header, and it lives in the Library Functions Manual. And what is it? It's a general purpose calculator for floats and 3D float vectors. That's the whole vibe. 🧮✨

heads up babes: this page is long, so it's rolling out in two parts. You're on part 1 right now. Pace yourself. 🫶

🌸 NAME 🌸

SoCalculator — a general purpose calculator for floats and 3D float vectors. Short name, big energy. 💅

✨ SYNOPSIS ✨

Pull it in like this, no cap:

#include <Inventor/engines/SoCalculator.h>

And it inherits SoEngine — so everything the SoEngine girlies can do, SoCalculator can do too. Family inheritance is lowkey the whole plot. 👑

💅 Public Member Functions

The main character's own moves:

virtual SoType getTypeId (void) const
virtual const SoFieldData * getFieldData (void) const
virtual const SoEngineOutputData * getOutputData (void) const
SoCalculator (void)

🫶 Public Member Functions inherited from `SoEngine`

These come free with the family 💖 you didn't write them, you just got them in the group chat:

void evaluateWrapper (void)
virtual int getOutputs (SoEngineOutputList &l) const
SoEngineOutput * getOutput (const SbName &outputname) const
SbBool getOutputName (const SoEngineOutput *output, SbName &outputname) const
SbBool isNotifying (void) const
virtual void notify (SoNotList *nl)
SoEngine * copy (void) const
virtual SoFieldContainer * copyThroughConnection (void) const
SbBool shouldCopy (void) const
virtual void writeInstance (SoOutput *out)

🎀 Public Member Functions inherited from `SoFieldContainer`

More inherited blessings ✨:

void setToDefaults (void)
SbBool hasDefaultValues (void) const
SbBool fieldsAreEqual (const SoFieldContainer *container) const
void copyFieldValues (const SoFieldContainer *container, SbBool copyconnections=0)
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 *in)
void get (SbString &fielddata, SoOutput *out)
virtual SbBool validateNewFieldValue (SoField *field, void *newval)
virtual void addWriteReference (SoOutput *out, SbBool isfromfield=0)
SbBool getIsBuiltIn (void) const
virtual void copyContents (const SoFieldContainer *from, SbBool copyconnections)
void setUserData (void *userdata) const
void * getUserData (void) const

🦋 Public Member Functions inherited from `SoBase`

The root of the whole ancestry tree, fr fr 🌳:

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)
virtual void startNotify (void)
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

The ones you can call without ever making an instance — very independent woman of them 💅:

static SoType getClassTypeId (void)
static void * createInstance (void)
static void initClass (void)

✨ Static Public Member Functions inherited from `SoEngine`

static void initClass (void)
static void initClasses (void)
static SoType getClassTypeId (void)
static SoEngine * getByName (const SbName &name)
static int getByName (const SbName &name, SoEngineList &el)

🌈 Static Public Member Functions inherited from `SoFieldContainer`

static void initClass (void)
static SoType getClassTypeId (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 *in, SoBase *&base, SoType expectedtype)
static void setInstancePrefix (const SbString &c)
static void setTraceRefs (SbBool trace)
static SbBool getTraceRefs (void)
static SbBool connectRoute (SoInput *in, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)
static SbBool readRoute (SoInput *in)

🔥 Public Attributes

This is the part where it gets spicy 🌶️ because look at this lineup.

First, the lowercase squad, all SoMFFloat:

SoMFFloat a
SoMFFloat b
SoMFFloat c
SoMFFloat d
SoMFFloat e
SoMFFloat f
SoMFFloat g
SoMFFloat h

Then the uppercase girlies, all SoMFVec3f — 3D float vector energy 👑:

SoMFVec3f A
SoMFVec3f B
SoMFVec3f C
SoMFVec3f D
SoMFVec3f E
SoMFVec3f F
SoMFVec3f G
SoMFVec3f H

And then the special ones 🥰:

SoMFString expression
SoEngineOutput oa
SoEngineOutput ob
SoEngineOutput oc
SoEngineOutput od
SoEngineOutput oA
SoEngineOutput oB
SoEngineOutput oC
SoEngineOutput oD

🌸 Protected Member Functions

For the inner circle only 🫶:

~SoCalculator (void)
virtual void inputChanged (SoField *which)

🧚 Protected Member Functions inherited from `SoEngine`

SoEngine (void)
virtual ~SoEngine ()
virtual SbBool readInstance (SoInput *in, unsigned short flags)
void writeOutputTypes (SoOutput *out)

🍓 Protected Member Functions inherited from `SoFieldContainer`

SoFieldContainer (void)
~SoFieldContainer ()

💀 Protected Member Functions inherited from `SoBase`

SoBase (void)
virtual ~SoBase ()
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 ** getInputDataPtr (void)
static const SoEngineOutputData ** getOutputDataPtr (void)

🎀 Static Protected Member Functions inherited from `SoEngine`

static const SoFieldData ** getInputDataPtr (void)
static const SoEngineOutputData ** getOutputDataPtr (void)

🦋 Static Protected Member Functions inherited from `SoBase`

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

🌟 Additional Inherited Members

The little bonus extras that came in the family bundle 💖

💜 Protected Types inherited from `SoBase`

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

🍓 Protected Attributes inherited from `SoFieldContainer`

SbBool isBuiltIn

…and that's a wrap on part 1, bestie 🫶 part 2 is loading, don't go anywhere. 🌈

✨ Detailed Description ✨

okay bestie, so SoCalculator is literally your general purpose calculator for floats and 3D float vectors. it's giving math engine energy, no cap. 💅

The SoCalculator uses the values from the input fields (which are either single floating point values or vectors) as variables in the free-form engine expressions and places the results on the output fields. the way that it just vibes with expressions? iconic.

The engine has sixteen input fields; eight scalar inputs (a, b, c, d, e, f, g, and h), and eight vector inputs (A, B, C, D, E, F, G, and H).

There are eight output fields; four scalar outputs (oa, ob, oc, and od), and four vector outputs (oA, oB, oC, and oD).

The expression syntax is quite similar to C/C++, with a very limited set of keywords and functions. it's giving baby C++ but make it calculator. 🎀

An example:

oa = a * (0.5 + b) / c

Will multiply the value in a with the value in b plus 0.5, divide that result with c, and place the result in oa. Since this is an engine, the expression will only be evaluated when someone attempts to read the value in oa, not every time an input in changed. lazy evaluation? we love to see it. 😭

All inputs are multi-fields, and if there are several values in an input, the expression will be evaluated once for every input field value, and the output will create as many values as there are input field values. so if you feed it a whole group chat, it replies to each message individually. periodt.

If there is more than one input field, and the input fields do not have the same number of values, the engine will create as many output values as the input field with the biggest number of values. When the index get out of bounds for some other input field, the last field value will be used. it's giving "main character field sets the pace". 👑

Vector expressions are similar to scalar expression. An example:

oA = A + vec3f(1.0, 0.0, 0.0) * B

Will take the vector in A, add the value in B multiplied with (1,0,0), and place the result in oA.

In addition to regular arithmetics, the SoCalculator syntax also includes some functions. so many little helpers, we're obsessed. 🫶

Scalar functions:

cos(x) — cosine function (x in radians)
sin(x) — sinus function
tan(x) — tangent function
acos(x) — arc cosine function
asin(x) — arc sinus function
atan(x) — arc tangent function
atan2(y, x) — arc tangent function of two variables (y, x).
cosh(x) — hyperbolic cosine function
sinh(x) — hyperbolic sinus function
tanh(x) — hyperbolic tangent function
sqrt(x) — square root function
pow(x,y) — x raised to the power of y
exp(x) — e to the power of x
log(x) — natural logarithm of x
log10() — base-10 logarithm of x
ceil(x) — rounds x upwards to the nearest integer
floor(x) — rounds x downwards to the nearest integer
fabs(x) — absolute value
fmod(x, y) — remainder of dividing x by y
rand(x) — pseudo-random value between 0 and 1

Vector functions:

cross(x, y) — cross product of x and y
dot(x,y) — dot product of x and y (returns scalar value)
length(x) — length of x (returns scalar value)
normalize(x) — returns normalized version of x
x[y] — access components in x (y should be a scalar value in the range [0,2])

There are also some named constants that can be used:

MAXFLOAT
MINFLOAT
M_E
M_LOG2E
M_LOG10E
M_LN2
M_PI
M_SQRT2 — sqrt(2)
M_SQRT1_2 — sqrt(1/2)

The only control flow available is the ? operator. An example:

oa = (a > b) ? (a * 0.5) : (b * c)

(The parentheses are not necessary, they're there just to make the example easier to read)

In addition to the standard comparators (<, >, <=, >=, ==, !=), you can also use && (AND) and || (OR) to combine expression, and the unary ! (NOT) operator.

One final thing worth mentioning is the temporary variables. There exists sixteen temporary variables that can be used in expressions. ta, tb, tc, td, te, tf, tg, and th are scalar variables, and tA, tB, tC, tD, tE, tF, tG, and tH are vector variables. They are usually used when you have more than one expression that should be evaluated in order. it's giving scratchpad energy. 📝

An example with three expressions:

ta = a * b; tb = c + d; tc = e - f
tA = vec3f(ta, tb, tc) + A
oA = tA * B

The example just shows how temporary variables can be used to make your expressions easier to read. Please note that it's possible to have several statements in one expression. You just separate them with semicolons.

Here is a simple example of how an SoCalculator engine may be used in an .iv file:

DEF mycamera PerspectiveCamera {
  orientation 1 0 0 1.57
}

DEF headlight DirectionalLight {
  intensity 0.8
  direction 0 0 1
}

Separator {
  # Render a cube not affected by lighting
  LightModel { model BASE_COLOR }
  BaseColor { rgb = Calculator {
                      a = USE headlight . intensity
                      expression [ "oA = vec3f( a, a, a)" ]
                    } . oA }
  Cube {}
}

In the example, the color of the Cube is a function of the intensity of the DirectionalLight, even though the Cube is rendered without lighting because of the BASE_COLOR LightModel. the way it just calculates the vibe check? slay. 🌈

🎀 Constructor & Destructor Documentation 🎀

`SoCalculator::SoCalculator (void )`

Constructor. it's born. 💖

References A, a, B, b, C, c, D, d, E, e, expression, F, f, G, g, H, h, oA, oa, oB, ob, oC, oc, oD, od, and SoCalculator().

Referenced by getFieldData(), and SoCalculator().

`SoCalculator::~SoCalculator (void )` [protected]

Destructor. it's giving farewell tour. 😭

💜 Member Function Documentation 💜

`SoType SoCalculator::getTypeId (void ) const` [virtual]

Returns the type identification of an object derived from a class inheriting SoBase. This is used for run-time type checking and "downward" casting. so you can be like "is this actually a SoFile? bestie check the ID." 🔍

Usage example:

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

Implements SoBase.

`const SoFieldData * SoCalculator::getFieldData (void ) const` [virtual]

Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL. no fields? returns NULL, which is giving "nothing to see here". 🙈

Reimplemented from SoFieldContainer.

References SoCalculator().

`const SoEngineOutputData * SoCalculator::getOutputData (void ) const` [virtual]

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer. iykyk, it's behind the scenes. 🎬

Implements SoEngine.

`void SoCalculator::inputChanged (SoField * which)` [protected], [virtual]

Called when an input is changed. The default method does nothing, but subclasses may override this method to do the The Right Thing when a specific field is changed. so if you're customizing, this is your moment. ✨

Reimplemented from SoEngine.

References expression.