Proteus VSM DLL Workflow Explained: Create Custom Simulation Models in C++

#include "pch.h"
#include <windows.h>
#include <string.h>   // for strcpy
#include <stdio.h>    // for sprintf
#include <math.h>     // for fabs
#include "vsm.hpp"

//-----------------------------------------------------------------------------
// Model class declaration
//-----------------------------------------------------------------------------
class my_device : public IACTIVEMODEL
{
public:
    my_device() : component(NULL), textstyle(NULL)
    {
        textorg.x = 0;
        textorg.y = 0;
        readout[0] = '\0';
    }

    VOID initialize(ICOMPONENT* cpt);
    ISPICEMODEL* getspicemodel(CHAR* device);
    IDSIMMODEL* getdsimmodel(CHAR* device);
    VOID plot(ACTIVESTATE state);
    VOID animate(INT element, ACTIVEDATA* newstate);
    BOOL actuate(WORD key, INT x, INT y, DWORD flags);

private:
    ICOMPONENT* component;
    POINT       textorg;
    HTEXTSTYLE  textstyle;
    CHAR        readout[10];
};

//-----------------------------------------------------------------------------
// Model construction and licensing
// (required boilerplate in every VSM DLL)
//-----------------------------------------------------------------------------

// --- DLL Export Functions ---
extern "C" __declspec(dllexport) IACTIVEMODEL* createactivemodel(CHAR* device, ILICENCESERVER* ils)
{
    return new my_device();
}

extern "C" __declspec(dllexport) VOID deleteactivemodel(IACTIVEMODEL* model)
{
    delete (my_device*)model;
}

// --- Implementation ---
//-----------------------------------------------------------------------------
// initialize()
// Called once, after licence authorization, to bind the model to its
// schematic component and set up the display's text origin/style.
//-----------------------------------------------------------------------------
VOID my_device::initialize(ICOMPONENT* cpt)
{
    // Store ICOMPONENT interface and initialize.
    component = cpt;

    // Get origin and style for readout text
    BOX textbox;
    cpt->getsymbolarea(1, &textbox);
    textorg.x = (textbox.left + textbox.right) / 2;
    textorg.y = (textbox.top + textbox.bottom) / 2;
    textstyle = cpt->createtextstyle((CHAR*)"ACTIVE READOUT");

    // Initial readout:
    strcpy(readout, " 0.00");
}

//-----------------------------------------------------------------------------
// Electrical interface stubs.
// READOUT is a purely graphical model - its electrical behaviour is provided
// externally by an RTVPROBE/RTIPROBE primitive (see the PRIMITIVE property
// on the library part), so these both return NULL.
//-----------------------------------------------------------------------------
ISPICEMODEL* my_device::getspicemodel(CHAR*) { return NULL; }
IDSIMMODEL* my_device::getdsimmodel(CHAR*) { return NULL; }

//-----------------------------------------------------------------------------
// plot()
// Called for a full, normal (non-animating) render of the component.
//-----------------------------------------------------------------------------
VOID my_device::plot(ACTIVESTATE state)
// Plot function - this is called for normal rendering.
{
    component->drawsymbol(-1);
    component->drawsymbol(1);
    component->drawtext(textorg.x, textorg.y, 0, TXJ_CENTRE | TXJ_MIDDLE, readout);
}

//-----------------------------------------------------------------------------
// animate()
// Called whenever the paired probe primitive produces a new reading.
// Only real-valued data is handled; the display is redrawn incrementally
// (just the my_device_1 panel + text, not the whole component).
//-----------------------------------------------------------------------------
VOID my_device::animate(INT element, ACTIVEDATA* data)
// Animate function - this is called whenever an event is
// produced by the simulator model.
// We interpret real values only, as follows:
{
    if (data->type == ADT_REAL)
    {
        // Decide whether to prefix with a +, a - or nothing:
        DOUBLE absval = fabs(data->realval);
        CHAR sign, result[10];
        if (data->realval > 0.001)
            sign = '+';
        else if (data->realval < -0.001)
            sign = '-';
        else
            sign = ' ';

        // Now we work out where to place the decimal point:
        if (absval >= 1000)
            sprintf(result, "%cMAX", sign);
        else if (absval >= 100)
            sprintf(result, "%c%3.0f", sign, absval);
        else if (absval >= 10)
            sprintf(result, "%c%4.1f", sign, absval);
        else
            sprintf(result, "%c%4.2f", sign, absval);

        // Finally, re-draw the display value within the result text
        // within it:
        component->drawsymbol(1);
        component->drawtext(textorg.x, textorg.y, 0,
            TXJ_CENTRE | TXJ_MIDDLE,
            strcpy(readout, result));
    }
}

//-----------------------------------------------------------------------------
// actuate()
// Mouse/keyboard event handler. READOUT is display-only, so it never
// consumes input events.
//-----------------------------------------------------------------------------
BOOL my_device::actuate(WORD key, INT x, INT y, DWORD flags)
{
    return FALSE;
}