pitrix/src/effect_firework.cpp

// Based on https://gist.github.com/kriegsman/68929cbd1d6de4535b20
#include "effect_firework.h"

FireworkEffectDot::FireworkEffectDot(Window* w, FireworkEffect* e) {
	_window = w;
	_main = e;
	show = 0;
	type = FIREWORK_DOT_NONE;
	_x = 0;
	_y = _window->height - 1;
	_xv = 0;
	_yv = 0;
	_r = 0;
	_color.setRGB(0, 0, 0);
}

void FireworkEffectDot::_screenscale(accum88 a, byte n, byte& screen, byte& screenerr) {
	byte ia = a >> 8;
	screen = scale8(ia, n);
	byte m = screen * (256 / n);
	screenerr = (ia - m) * scale8(255, n);
}

int16_t FireworkEffectDot::_scale15by8_local(int16_t i, fract8 scale) {
	int16_t result;
	result = (int32_t)((int32_t) i*scale)/256;
	return result;
}

void FireworkEffectDot::draw() {
	if (!show) return;
	byte ix, xe, xc;
	byte iy, ye, yc;
	_screenscale(_x, _window->width, ix, xe);
	_screenscale(_y, _window->height, iy, ye);
	xc = 255 - xe;
	yc = 255 - ye;

	CRGB c00 = CRGB(dim8_video( scale8( scale8( _color.r, yc), xc)),
	                dim8_video( scale8( scale8( _color.g, yc), xc)),
	                dim8_video( scale8( scale8( _color.b, yc), xc)));
	CRGB c01 = CRGB(dim8_video( scale8( scale8( _color.r, ye), xc)),
	                dim8_video( scale8( scale8( _color.g, ye), xc)),
	                dim8_video( scale8( scale8( _color.b, ye), xc)));
	CRGB c10 = CRGB(dim8_video( scale8( scale8( _color.r, yc), xe)),
	                dim8_video( scale8( scale8( _color.g, yc), xe)),
	                dim8_video( scale8( scale8( _color.b, yc), xe)));
	CRGB c11 = CRGB(dim8_video( scale8( scale8( _color.r, ye), xe)),
	                dim8_video( scale8( scale8( _color.g, ye), xe)),
	                dim8_video( scale8( scale8( _color.b, ye), xe)));
	_window->addPixelColor(ix, iy, &c00);
	_window->addPixelColor(ix, iy-1, &c01);
	_window->addPixelColor(ix+1, iy, &c10);
	_window->addPixelColor(ix+1, iy-1, &c11);
}

void FireworkEffectDot::move() {
	if (!show) return;
	_yv -= settings.effects.firework.gravity;
	_xv = _scale15by8_local(_xv, settings.effects.firework.drag);
	_yv = _scale15by8_local(_yv, settings.effects.firework.drag);

	if (type == FIREWORK_DOT_SPARK) {
		_xv = _scale15by8_local(_xv, settings.effects.firework.drag);
		_yv = _scale15by8_local(_yv, settings.effects.firework.drag);
		_color.nscale8(255);
		if (!_color) {
			show = 0;
		}
	}

	// Bounce if we hit the ground
	if (_yv < 0 && _y - _window->height < (-_yv)) {
		if (type == FIREWORK_DOT_SPARK) {
			show = 0;
		} else {
			_yv = -_yv;
			_yv = _scale15by8_local(_yv, settings.effects.firework.bounce);
			if (_yv < 500) {
				show = 0;
			}
		}
	}

	if (_yv < 300) {
		if (type == FIREWORK_DOT_SHELL) {
			if (_y < (uint16_t)0x8000) {
				// boom
				CRGB white(0xFFFFFF);
				_window->clear(&white);
			}
			show = 0;
			_main->skyburst(_x, _y, _xv, _yv, _color);
		}
	}

	if (type == FIREWORK_DOT_SPARK) {
		if ((_xv > 0 && _x>_xv) || (_xv < 0 && _x<(0xFFFF+_xv))) {
			_x += _xv;
		} else {
			show = 0;
		}
	} else {
		_x += _xv;
	}
	_y -= _yv;
}

void FireworkEffectDot::ground_launch() {
	_xv = (int16_t)random16(600) - (int16_t)300;
	_yv = 600 + random16(300 + (25 * _window->height));
	_x = 0x8000;
	_y = 0;
	hsv2rgb_rainbow(CHSV(random8(), 240, 200), _color);
	show = 1;
}

void FireworkEffectDot::sky_burst(accum88 basex, accum88 basey, saccum78 basedv, CRGB& basecolor) {
	_xv = basedv + (int16_t)random16(2000) - (int16_t)1000;
	_yv = (int16_t)random16(1500) - (int16_t)500;
	_x = basex;
	_y = basey;
	_color = basecolor;
	_color *= 4;
	type = FIREWORK_DOT_SPARK;
	show = 1;
}

void FireworkEffect::skyburst(accum88 x, accum88 y, saccum78 xv, saccum78 yv, CRGB c) {
	_skyburst = 1;
	_burst_x = x;
	_burst_y = y;
	_burst_xv = xv;
	_burst_yv = yv;
	_burst_color = c;
}

boolean FireworkEffect::can_be_shown_with_clock() {
	return true;
}

void FireworkEffect::loop(uint16_t ms) {
	window->clear();
	_dot->move();
	_dot->draw();
	for (int i=0; i<settings.effects.firework.sparks; i++) {
		_sparks[i]->move();
		_sparks[i]->draw();
	}
	static uint16_t launch_countdown = 0;
	if (_dot->show == 0) {
		if (launch_countdown == 0) {
			_dot->ground_launch();
			_dot->type = FIREWORK_DOT_SHELL;
			launch_countdown = random16(350) + 1;
		} else {
			launch_countdown--;
		}
	}

	if (_skyburst) {
		int nsparks = random8(settings.effects.firework.sparks / 2, settings.effects.firework.sparks + 1);
		for (int i=0; i<nsparks; i++) {
			_sparks[i]->sky_burst(_burst_x, _burst_y, _burst_yv, _burst_color);
			_skyburst = 0;
		}
	}
}

FireworkEffect::FireworkEffect() {
	_dot = new FireworkEffectDot(window, this);
	_sparks = new FireworkEffectDot*[settings.effects.firework.sparks];
	for (int i=0; i<settings.effects.firework.sparks; i++) {
		_sparks[i] = new FireworkEffectDot(window, this);
	}
}

FireworkEffect::~FireworkEffect() {
	for (int i=0; i<settings.effects.firework.sparks; i++) {
		delete _sparks[i];
	}
	delete _dot;
}