The-Powder-Toy/src/simulation/elements/PSTN.cpp

#include "simulation/Elements.h"
//#TPT-Directive ElementClass Element_PSTN PT_PSTN 168
Element_PSTN::Element_PSTN()
{
    Identifier = "DEFAULT_PT_PSTN";
    Name = "PSTN";
    Colour = PIXPACK(0xAA9999);
    MenuVisible = 1;
    MenuSection = SC_FORCE;
    Enabled = 1;
    
    Advection = 0.0f;
    AirDrag = 0.00f * CFDS;
    AirLoss = 0.90f;
    Loss = 0.00f;
    Collision = 0.0f;
    Gravity = 0.0f;
    Diffusion = 0.00f;
    HotAir = 0.000f	* CFDS;
    Falldown = 0;
    
    Flammable = 0;
    Explosive = 0;
    Meltable = 0;
    Hardness = 0;
    
    Weight = 100;
    
    Temperature = R_TEMP+0.0f +273.15f;
    HeatConduct = 0;
    Description = "Piston, extends and pushes particles";
    
    State = ST_SOLID;
    Properties = TYPE_SOLID|PROP_LIFE_DEC;
    
    LowPressure = IPL;
    LowPressureTransition = NT;
    HighPressure = IPH;
    HighPressureTransition = NT;
    LowTemperature = ITL;
    LowTemperatureTransition = NT;
    HighTemperature = ITH;
    HighTemperatureTransition = NT;
    
    Update = &Element_PSTN::update;
    Graphics = &Element_PSTN::graphics;
    
}

//#TPT-Directive ElementHeader Element_PSTN static int tempParts[128];
int Element_PSTN::tempParts[128];
//#TPT-Directive ElementHeader Element_PSTN static int tempPartAmount[128];
int Element_PSTN::tempPartAmount[128];

#define PISTON_INACTIVE		0x00
#define PISTON_RETRACT		0x01
#define PISTON_EXTEND		0x02
#define MAX_FRAME			0x0F
#define DEFAULT_LIMIT		0x1F
#define DEFAULT_ARM_LIMIT	0xFF

//#TPT-Directive ElementHeader Element_PSTN static int update(UPDATE_FUNC_ARGS)
int Element_PSTN::update(UPDATE_FUNC_ARGS)
 {
 	if(parts[i].ctype)
 		return 0;
 	int maxSize = parts[i].tmp ? parts[i].tmp : DEFAULT_LIMIT;
 	int armLimit = parts[i].tmp2 ? parts[i].tmp2 : DEFAULT_ARM_LIMIT;
 	int state = 0;
	int r, nxx, nyy, nxi, nyi, rx, ry;
	int directionX = 0, directionY = 0;
	if (parts[i].life==0 && state == PISTON_INACTIVE) {
		for (rx=-2; rx<3; rx++)
			for (ry=-2; ry<3; ry++)
				if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry) && (!rx || !ry))
				{
					r = pmap[y+ry][x+rx];
					if (!r)
						continue;
					if ((r&0xFF)==PT_SPRK && parts[r>>8].life==3) {
						if(parts[r>>8].ctype == PT_PSCN)
							state = PISTON_EXTEND;
						else
							state = PISTON_RETRACT;
					}
				}
	}
	if(state == PISTON_EXTEND || state == PISTON_RETRACT) {
		for (rx=-1; rx<2; rx++)
			for (ry=-1; ry<2; ry++)
				if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry) && (!rx || !ry))
				{
					r = pmap[y+ry][x+rx];
					if (!r)
						continue;
					if ((r&0xFF) == PT_PSTN) {
						bool movedPiston = false;
						directionX = rx;
						directionY = ry;
						{
							bool foundEnd = false;
							int pistonEndX, pistonEndY;
							int pistonCount = 0;
							int newSpace = 0;
							int armCount = 0;
							for (nxx = 0, nyy = 0, nxi = directionX, nyi = directionY; ; nyy += nyi, nxx += nxi) {
								if (!(x+nxi+nxx<XRES && y+nyi+nyy<YRES && x+nxi+nxx >= 0 && y+nyi+nyy >= 0)) {
									break;
								}
								r = pmap[y+nyi+nyy][x+nxi+nxx];
								if((r&0xFF)==PT_PSTN) {
									if(parts[r>>8].ctype)
										armCount++;
									else if (armCount)
									{
										pistonEndX = x+nxi+nxx;
										pistonEndY = y+nyi+nyy;
										foundEnd = true;
										break;
									}
									else
										pistonCount++;
								} else {
									pistonEndX = x+nxi+nxx;
									pistonEndY = y+nyi+nyy;
									foundEnd = true;
									break;
								}
							}
							if(foundEnd) {
								if(state == PISTON_EXTEND) {
									if(armCount+pistonCount > armLimit)
										pistonCount = armLimit-armCount;
									if(pistonCount > 0) {
										newSpace = MoveStack(sim, pistonEndX, pistonEndY, directionX, directionY, maxSize, pistonCount, false);
										if(newSpace) {
											//Create new piston section
											for(int j = 0; j < newSpace; j++) {
												int nr = sim->create_part(-3, pistonEndX+(nxi*j), pistonEndY+(nyi*j), PT_PSTN);
												if (nr!=-1) {
													parts[nr].ctype = 1;
												}
											}
											movedPiston =  true;
										}
									}
								} else if(state == PISTON_RETRACT) {
									if(pistonCount > armCount)
										pistonCount = armCount;
									if(armCount) {
										//Remove arm section
										int lastPistonX = pistonEndX - nxi;	//Go back to the very last piston arm particle
										int lastPistonY = pistonEndY - nyi;
										for(int j = 0; j < pistonCount; j++) {
											sim->delete_part(lastPistonX+(nxi*-j), lastPistonY+(nyi*-j), 0);
										}
										MoveStack(sim, pistonEndX, pistonEndY, directionX, directionY, maxSize, pistonCount, true);
										//newSpace = MoveStack(sim, pistonEndX, pistonEndY, directionX, directionY, maxSize, pistonCount, true);
										movedPiston = true;
									}
								}
							}
						}

						if (movedPiston)
							break;
					}
				}

	}
	return 0;
}

//#TPT-Directive ElementHeader Element_PSTN static int CanMoveStack(Simulation * sim, int stackX, int stackY, int directionX, int directionY, int size, int amount)
int Element_PSTN::CanMoveStack(Simulation * sim, int stackX, int stackY, int directionX, int directionY, int size, int amount)
{
	int posX, posY, r, spaces = 0, currentPos = 0;
	if (amount == 0)
		return 0;
	for(posX = stackX, posY = stackY; currentPos < size + amount; posX += directionX, posY += directionY) {
		if (!(posX < XRES && posY < YRES && posX >= 0 && posY >= 0)) {
			break;
		}
		r = sim->pmap[posY][posX];
		if (sim->IsWallBlocking(posX, posY, 0)/* || (r&0xFF) == PT_INSL*/)
			break;
		if(!r) {
			spaces++;
			tempParts[currentPos++] = -1;
			if(spaces >= amount)
				break;
		} else {
			if(currentPos < size)
				tempParts[currentPos++] = r>>8;
			else
				return spaces;
		}
	}
	if (spaces)
		return currentPos;
	else
		return 0;
}

//#TPT-Directive ElementHeader Element_PSTN static int MoveStack(Simulation * sim, int stackX, int stackY, int directionX, int directionY, int size, int amount, bool retract, int callDepth = 0)
int Element_PSTN::MoveStack(Simulation * sim, int stackX, int stackY, int directionX, int directionY, int size, int amount, bool retract, int callDepth)
{
	bool foundParts = false;
	int posX, posY, r, spaces = 0, currentPos = 0;
	r = sim->pmap[stackY][stackX];
	if(!callDepth && (r&0xFF) == PT_FRME) {
		int ret = amount;
		int newY = !!directionX, newX = !!directionY;
		if (!retract)
		{
			//check if we can push all the FRME
			for(int c = 0; c < MAX_FRAME; c++) {
				posY = stackY + (c*newY);
				posX = stackX + (c*newX);
				if (posX < XRES && posY < YRES && posX >= 0 && posY >= 0 && (sim->pmap[posY][posX]&0xFF) == PT_FRME) {
					int val = CanMoveStack(sim, posX+directionX, posY+directionY, directionX, directionY, size, amount);
					if(val < amount)
						amount = val;
				} else
					break;
			}
			for(int c = 1; c < MAX_FRAME; c++) {
				posY = stackY - (c*newY);
				posX = stackX - (c*newX);
				if (posX < XRES && posY < YRES && posX >= 0 && posY >= 0 && (sim->pmap[posY][posX]&0xFF) == PT_FRME) {
					int val = CanMoveStack(sim, posX+directionX, posY+directionY, directionX, directionY, size, amount);
					if(val < amount)
						amount = val;
				} else
					break;
			}
		}
		//If the piston is pushing frame, iterate out from the centre to the edge and push everything resting on frame
		for(int c = 0; c < MAX_FRAME; c++) {
			posY = stackY + (c*newY);
			posX = stackX + (c*newX);
			if (posX < XRES && posY < YRES && posX >= 0 && posY >= 0) {
				r = sim->pmap[posY][posX];
				if((r&0xFF) == PT_FRME) {
					int val = MoveStack(sim, posX, posY, directionX, directionY, size, amount, retract, 1);
					if(c == 0)
						ret = val;
				} else
					break;
			}
		} 
		for(int c = 1; c < MAX_FRAME; c++) {
			posY = stackY - (c*newY);
			posX = stackX - (c*newX);
			if (posX < XRES && posY < YRES && posX >= 0 && posY >= 0) {
				r = sim->pmap[posY][posX];
				if((r&0xFF) == PT_FRME) {
					MoveStack(sim, posX, posY, directionX, directionY, size, amount, retract, 1);
				} else
					break;
			}
		}
		return ret;
	}
	if(retract){
		bool foundEnd = false;
		//Warning: retraction does not scan to see if it has space
		for(posX = stackX, posY = stackY; currentPos < size; posX += directionX, posY += directionY) {
			if (!(posX < XRES && posY < YRES && posX >= 0 && posY >= 0)) {
				break;
			}
			r = sim->pmap[posY][posX];
			if(!r) {
				break;
			} else {
				foundParts = true;
				tempParts[currentPos++] = r>>8;
			}
		}
		if(foundParts) {
			//Move particles
			for(int j = 0; j < currentPos; j++) {
				int jP = tempParts[j];
				sim->pmap[(int)(sim->parts[jP].y + 0.5f)][(int)(sim->parts[jP].x + 0.5f)] = 0;
				sim->parts[jP].x += (float)((-directionX)*amount);
				sim->parts[jP].y += (float)((-directionY)*amount);
				sim->pmap[(int)(sim->parts[jP].y + 0.5f)][(int)(sim->parts[jP].x + 0.5f)] = sim->parts[jP].type|(jP<<8);
			}
			return amount;
		}
		if(!foundParts && foundEnd)
			return amount;
	} else {
		currentPos = CanMoveStack(sim, stackX, stackY, directionX, directionY, size, amount);
		if(currentPos){
			//Move particles
			int possibleMovement = 0;
			for(int j = currentPos-1; j >= 0; j--) {
				int jP = tempParts[j];
				if(jP == -1) {
					possibleMovement++;
					continue;
				}
				if(!possibleMovement)
					continue;
				sim->pmap[(int)(sim->parts[jP].y + 0.5f)][(int)(sim->parts[jP].x + 0.5f)] = 0;
				sim->parts[jP].x += (float)(directionX*possibleMovement);
				sim->parts[jP].y += (float)(directionY*possibleMovement);
				sim->pmap[(int)(sim->parts[jP].y + 0.5f)][(int)(sim->parts[jP].x + 0.5f)] = sim->parts[jP].type|(jP<<8);
			}
			return possibleMovement;
		}
		if(!foundParts && spaces)
			return spaces;
	}
	return 0;
}


//#TPT-Directive ElementHeader Element_PSTN static int graphics(GRAPHICS_FUNC_ARGS)
int Element_PSTN::graphics(GRAPHICS_FUNC_ARGS)
{
	if(cpart->ctype)
	{
		*colr -= 60;
		*colg -= 60;
	}
	return 0;
}

Element_PSTN::~Element_PSTN() {}