SOCALCULATOR(3iv)

💖 SoCalculator(3IV) 💖

okay bestie, buckle up, because this is the manual page for SoCalculator from the (3IV) section of the docs, and it is literally a whole calculator engine that lives inside your scene graph. no cap. let's get into it 🫶

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🌸 NAME 🌸

SoCalculator — a general-purpose calculator 💅

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🧬 INHERITS FROM 🧬

SoBase > SoFieldContainer > SoEngine > SoCalculator

it's giving a whole ancestry tree, and yes, it inherits everything from every one of those. iconic lineage honestly 👑

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✨ SYNOPSIS ✨

#include <Inventor/engines/SoCalculator.h>

Inputs from class SoCalculator:

SoMFFloat           a
SoMFFloat           b
SoMFFloat           c
SoMFFloat           d
SoMFFloat           e
SoMFFloat           f
SoMFFloat           g
SoMFFloat           h
SoMFVec3f           A
SoMFVec3f           B
SoMFVec3f           C
SoMFVec3f           D
SoMFVec3f           E
SoMFVec3f           F
SoMFVec3f           G
SoMFVec3f           H
SoMFString          expression

Outputs from class SoCalculator:

(SoMFFloat)         oa
(SoMFFloat)         ob
(SoMFFloat)         oc
(SoMFFloat)         od
(SoMFVec3f)         oA
(SoMFVec3f)         oB
(SoMFVec3f)         oC
(SoMFVec3f)         oD

Methods from class SoCalculator:

                    SoCalculator()

Methods from class SoEngine:

static SoType       getClassTypeId()
virtual int         getOutputs(SoEngineOutputList &list) const
SoEngineOutput *    getOutput(const SbName &outputName) const
SbBool              getOutputName(const SoEngineOutput *output, SbName
                         &outputName) const
SoEngine *          copy() const
static SoEngine *   getByName(const SbName &name)
static int          getByName(const SbName &name, SoEngineList &list)

Methods from class SoFieldContainer:

void                setToDefaults()
SbBool              hasDefaultValues() const
SbBool              fieldsAreEqual(const SoFieldContainer *fc) const
void                copyFieldValues(const SoFieldContainer *fc, SbBool
                         copyConnections = FALSE)
SbBool              set(const char *fieldDataString)
void                get(SbString &fieldDataString)
virtual int         getFields(SoFieldList &resultList) const
virtual SoField *   getField(const SbName &fieldName) const
SbBool              getFieldName(const SoField *field, SbName &fieldName)
                         const
SbBool              isNotifyEnabled() const
SbBool              enableNotify(SbBool flag)

Methods from class SoBase:

void                ref()
void                unref() const
void                unrefNoDelete() const
void                touch()
virtual SoType      getTypeId() const
SbBool              isOfType(SoType type) const
virtual void        setName(const SbName &name)
virtual SbName      getName() const

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📝 DESCRIPTION 📝

so this engine? it's a general-purpose calculator. like, a full-on math girlie living inside your engine tree. 🧮✨ It operates on floating-point values and 3D floating-point vectors. The engine takes up to eight inputs of each type (SoMFFloat and SoMFVec3f), and produces up to four outputs of each type.

Each input field (a-h, A-H) can have multiple values, which lets the engine evaluate the expression with different values in parallel. lowkey multitasking queen. Some inputs may have more values than others. In such cases, the last value of the shorter inputs will be repeated as necessary — it just keeps recycling that last value, periodt.

The expression input string specifies the expression to be evaluated. An expression can consist of multiple subexpressions. Several subexpressions can be specified in one string, separated by semicolons (;). Alternatively, the subexpressions can be stored in separate strings in the multiple-valued input field. either way bestie, you choose.

Each subexpression is of the form:

<lhs> = <rhs>

The <lhs> can be any one of the outputs or a temporary variable. The engine provides 8 temporary floating-point variables (ta, tb, tc, td, te, tf, tg, and th), and 8 temporary vector variables (tA, tB, tC, tD, tE, tF, tG, and tH). You can assign a value to one component of a vector output (A-H) or a vector variable (tA-tH) by using the [] operator. For example, oA[0] = <rhs>, will evaluate the right hand side and assign the value to the first component of the output vector oA. ✨

The <rhs> supports arithmetic, logical and conditional operators. They are:

(unary)   !, -
(binary)  +, -, *, /, %, <, > <=, >=, ==, !=, &&, ||
(ternary) ? :

The ternary operator is a conditional operator. For example, a ? b : c evaluates to b if a != 0, and to c if a==0. it's giving choose-your-own-adventure, but make it math 💅

Valid operands for the <rhs> include the inputs, outputs, temporary variables, and their components (e.g. oA[0]). Operands can also be numeric constants (e.g. 1.0), pre-defined named constants, or pre-defined functions.

The named constants are:

MAXFLOAT
MINFLOAT
M_E
M_LOG2E
M_LOG10E
M_LN2
M_LN10
M_PI
M_SQRT2  = sqrt(2)
M_SQRT1_2 = sqrt(1/2)

Most of the pre-defined functions come from the math library:

cos, sin, tan,
acos, asin, atan, atan2,
cosh, sinh, tanh,
sqrt, pow, exp, log, log10,
ceil, floor, fabs, fmod.

Other functions are defined by SoCalculator. They are:

rand(f) - Random number generator
cross(v1, v2) - Vector cross product
dot(v1, v2) - Vector dot product
length(v) - Vector length
normalize(v) - Normalize vector
vec3f(f1, f2, f3) - Generate a vector from 3 floats

The subexpressions are evaluated in order, so a variable set in the <lhs> of an earlier expression may be used in the <rhs> of a later expression. chronological order girlies, respect the timeline 🕰️

⚠️ Note, when the input has multiple values, all the subexpressions specified in the expression are applied to all the multiple input values. This is unlike the SoBoolOperation engine, where each operation is applied only to the corresponding entries of the input data. Note also, that even though the inputs and outputs can have multiple values the [] operator is only for indexing into the values of a single vector. It does not index into the multiple values of a field.

like, for example, if the floating-point input field a has two values: 1.0, and 2.0, then the expression

"oA[0]=a; oA[1]=a; oA[2]=0.0"

will produce two output vectors in oA: (1.0, 1.0, 0.0) and (2.0, 2.0, 0.0). see how that works?? the way it just... does that 😭🔥

Examples of expressions:

"ta = oA[0]*floor(a)"
"tb = (a+b)*sin(M_PI)"
"oA = vec3f(ta, tb, ta+tb)"
"oB = normalize(oA)"
"ta = a; tb = sin(ta); oA = vec3f(ta, tb, 0)"

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🎀 INPUTS 🎀

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

Inputs a-h are the floating-point values. 🍓

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

Inputs A-H are the vectors. 💜

• SoMFString expression

The expression to be evaluated. ✨

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🌈 OUTPUTS 🌈

• (SoMFFloat) oa
• (SoMFFloat) ob
• (SoMFFloat) oc
• (SoMFFloat) od

Outputs oa-od are the floating-point values. 💖

• (SoMFVec3f) oA
• (SoMFVec3f) oB
• (SoMFVec3f) oC
• (SoMFVec3f) oD

Outputs oA-oD are the vectors. 🦋

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🛠️ METHODS 🛠️

• SoCalculator() — Constructor. the origin story, the main character entrance 👑

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📁 FILE FORMAT/DEFAULTS 📁

Calculator {
   a           0
   b           0
   c           0
   d           0
   e           0
   f           0
   g           0
   h           0
   A           0 0 0
   B           0 0 0
   C           0 0 0
   D           0 0 0
   E           0 0 0
   F           0 0 0
   G           0 0 0
   H           0 0 0
   expression  ""
}

everything starts at zero and the expression starts empty, so it's a total blank slate bestie, a fresh notebook, a clean canvas, we love a fresh start 🌸

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👀 SEE ALSO 👀

• SoEngineOutput
• SoBoolOperation

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and that's the whole page, bestie!! 🫶✨ this was the SoCalculator(3IV) manual page, living its life in section 3IV of the docs — and yeah, the footer just echoes that same SoCalculator(3IV) name right back at you, so consider yourself properly signed off. go forth and calculate, you absolute icon 👑💅🔥