simple.cpp

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// Summary: Very simple demo program for flatland.
// Copyright: 2007  Philip Rideout.  All rights reserved.
// License: see bsd-license.txt

#include <ode/ode.h>
#include "demo.hpp"
#include "os.h"

using namespace Demo;

const int MaxObjects = 400;

static void AddFallingObject(Space &space, Object *object);

/// Entry point.
int main(int argc, char** argv)
{
    int width = 800;
    int height = 600;

    osInit(width, height, 0, 0);

    // Instantiate the app object.
    App app(width, height);
    app.InitGl();
    app.InitOde();

    // Insert some objects into the space.
    Space &space = app.GetSpace();
    space << new Demo::Line(vec2(0, 600), vec2(800, 600));
    space << new Demo::Line(vec2(800, 0), vec2(800, 600));
    space << new Demo::Line(vec2(0, 0), vec2(0, 600));
    {
        Wheel *wheel = new Wheel(vec2(390, 550), 50);
        wheel->GetFlatlandObject()->SetMass(5000);
        wheel->Property().outlineThickness = 1;
        wheel->Insert(space);
    }
    space.mark();

     // Upper limit on frames-per-second.
    const float fps = 60.0;

    // Simulation step size; proportional to speed and inversely proportional to precision.
    const float delta = 0.25;

    // Set up some time variables.  Time is measured in milliseconds.
    unsigned int currentTime = osGetMilliseconds();
    unsigned int previousSampleTime = currentTime;
    unsigned int previousDrawTime = currentTime;
    const unsigned int sampleDelay = 5000;
    const unsigned int drawDelay = (unsigned int) (1000.0 / fps);

    // Count the simulation "steps" (iterations) since the last performance sample.
    unsigned int stepCount = 0;

    // Main simulation loop.
    OS_Event event;
    for (;;)
    {
        // process all events
        while (osPollEvent(&event))
        {
            switch(event.type)
            {
                case OS_QUIT: exit(0);
                case OS_KEYUP:
                    switch (event.key.key)
                    {
                        case 'x': case 'X': case 'q': case 'Q':
                        case OSK_ESCAPE: exit(0);
                    }
            }
        }

        // update the clock
        currentTime = osGetMilliseconds();

        // take a performance sample and calculate the steps-per-millisecond
        if (space.size() == MaxObjects && currentTime - previousSampleTime > sampleDelay)
        {
            double spms = (double) stepCount / (double) (currentTime - previousSampleTime);
            previousSampleTime = currentTime;
            stepCount = 0;
            printf("%d\n", spms);
        }

        // draw the scene and do a page flip
        if (currentTime - previousDrawTime > drawDelay)
        {
            app.Draw();
            osSwapBuffers();
            previousDrawTime = currentTime;
        }

        // update the simulation
        app.Step(delta);
        ++stepCount;

        // add a new block or ball every now and then
        if (space.size() < MaxObjects)
        {
            if (!(stepCount % 100))
                AddFallingObject(space, new Ball(vec2(400, 0), 15));
            if (!((stepCount + 50) % 100))
                AddFallingObject(space, new Block(vec2(400, 0), 20, 20));
        }
    }

    return 0;
}

/// Assigns a color to an object and adds it to the space.
void AddFallingObject(Space &space, Object *object)
{
    if (space.size() >= MaxObjects)
        space.pop();

    Color pastel(60.0f + (rand() % 90) - 45);
    object->Property().outlineColor = pastel;
    pastel.IncreaseBrightness(0.5);
    object->Property().fillColor = pastel;
    object->Property().outlineThickness = 1;
    space.push_back(object);
}

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