borgware-2d/animations/laborlogo.c

#include <stdint.h>
#include <assert.h>
#include "../compat/pgmspace.h"
#include "../random/prng.h"
#include "../util.h"
#include "../autoconf.h"
#include "../pixel.h"

#define PRB(a) pgm_read_byte(&(a))

#define BITMAP_WIDTH   48
#define BITMAP_HEIGHT  48
#define VIEWPORT_WIDTH  16
#define VIEWPORT_HEIGHT 16
#define XDOMAIN (BITMAP_WIDTH - VIEWPORT_WIDTH)
#define YDOMAIN (BITMAP_HEIGHT - VIEWPORT_HEIGHT)
#define FRAME_TICK 75
#define FRAMECOUNT 400

static uint16_t laborlogo_getLine(const uint8_t x,
                                  const uint8_t y)
{
	assert(x <= BITMAP_WIDTH - VIEWPORT_WIDTH);
	assert(y < BITMAP_HEIGHT);

	static const uint8_t nBitmap[48][6] PROGMEM =
			{{0xFF, 0xFF, 0xE0, 0x07, 0xFF, 0xFF},
			 {0xFF, 0xFF, 0x00, 0xF8, 0xFF, 0xFF},
			 {0xFF, 0xF8, 0x00, 0xFF, 0x1F, 0xFF},
			 {0xFF, 0xF0, 0x00, 0xFF, 0xEF, 0xFF},
			 {0xFF, 0xC0, 0x00, 0xFF, 0xF3, 0xFF},
			 {0xFF, 0x80, 0x00, 0xFF, 0xFD, 0xFF},
			 {0xFF, 0x00, 0x00, 0xFF, 0xFE, 0xFF},
			 {0xFE, 0x00, 0x03, 0x3F, 0xFF, 0x7F},
			 {0xFC, 0x00, 0x04, 0xDF, 0xFF, 0xBF},
			 {0xF8, 0x00, 0x08, 0xEF, 0xFF, 0xDF},
			 {0xF0, 0x00, 0x10, 0xF7, 0xFF, 0xEF},
			 {0xF0, 0x00, 0x10, 0xF7, 0xFF, 0xEF},
			 {0xE0, 0xC0, 0x10, 0xF7, 0xFF, 0xF7},
			 {0xC0, 0xC0, 0x10, 0xF7, 0xFF, 0xFB},
			 {0xC0, 0x40, 0x08, 0xEF, 0xFF, 0xFB},
			 {0xC0, 0x40, 0x04, 0xDF, 0xFF, 0xFB},
			 {0x80, 0x40, 0x03, 0x3F, 0xFF, 0xFD},
			 {0x87, 0xFC, 0x00, 0xFF, 0xFF, 0xFD},
			 {0x84, 0x0C, 0x00, 0xFF, 0xFF, 0xFD},
			 {0x04, 0x00, 0x1F, 0x07, 0xFF, 0xFE},
			 {0x04, 0x00, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x04, 0x00, 0x10, 0xF7, 0xFF, 0xFE},
			 {0xFF, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0x00, 0x80, 0x10, 0xF7, 0xFF, 0xFE},
			 {0xBF, 0xFC, 0x10, 0xF7, 0xFF, 0xFD},
			 {0xB0, 0x0C, 0x10, 0xF7, 0xFF, 0xFD},
			 {0x80, 0x00, 0x10, 0xF7, 0xFF, 0xFD},
			 {0xC0, 0x00, 0x10, 0xF7, 0xFF, 0xFB},
			 {0xC0, 0x00, 0x10, 0xF7, 0xFF, 0xFB},
			 {0xC0, 0x00, 0x10, 0xF7, 0xFF, 0xFB},
			 {0xE0, 0x00, 0x10, 0xF7, 0xFF, 0xF7},
			 {0xF0, 0x00, 0x10, 0xF7, 0xFF, 0xEF},
			 {0xF0, 0x00, 0x10, 0xF7, 0xFF, 0xEF},
			 {0xF8, 0x00, 0x10, 0xF7, 0xFF, 0xDF},
			 {0xFC, 0x00, 0x10, 0xF7, 0xFF, 0xBF},
			 {0xFE, 0x00, 0x1F, 0x07, 0xFF, 0x7F},
			 {0xFF, 0x00, 0x00, 0xFF, 0xFE, 0xFF},
			 {0xFF, 0x80, 0x00, 0xFF, 0xFD, 0xFF},
			 {0xFF, 0xC0, 0x00, 0xFF, 0xF3, 0xFF},
			 {0xFF, 0xF0, 0x00, 0xFF, 0xEF, 0xFF},
			 {0xFF, 0xF8, 0x00, 0xFF, 0x1F, 0xFF},
			 {0xFF, 0xFF, 0x00, 0xF8, 0xFF, 0xFF},
			 {0xFF, 0xFF, 0xE0, 0x07, 0xFF, 0xFF}};

	uint16_t nLine;
	uint8_t nAlignment = x % 8;

	if (nAlignment == 0)
	{
		nLine = PRB(nBitmap[y][x / 8]) << 8;
		nLine |= PRB((nBitmap[y][x / 8 + 1]));
	}
	else
	{
		nLine = PRB(nBitmap[y][x / 8]) << (8 + nAlignment);
		nLine |= PRB(nBitmap[y][x / 8 + 1]) << nAlignment;
		nLine |= PRB(nBitmap[y][x / 8 + 2]) >> (8 - nAlignment);
	}

	return nLine;
}


static void laborlogo_drawViewport(const uint8_t nBitmapX,
                                   const uint8_t nBitmapY)
{
	assert(nBitmapX <= XDOMAIN);
	assert(nBitmapY <= YDOMAIN);

	for (uint8_t nVPortY = 0; nVPortY < 16; ++nVPortY)
	{
		uint16_t nLineBuffer = laborlogo_getLine(nBitmapX, nVPortY + nBitmapY);
		for (int8_t nVPortX = 0; nVPortX < 16; ++nVPortX)
		{
			if ((0x0001 << nVPortX) & nLineBuffer)
			{
				setpixel((pixel){nVPortX, nVPortY}, 3);
			}
			else
			{
				setpixel((pixel){nVPortX, nVPortY}, 0);
			}
		}
	}
}

static void laborlogo_recalcVectors(const int8_t x,
                                    const int8_t y,
                                    int8_t *const pdx,
                                    int8_t *const pdy)
{
	if (((x + *pdx) > (XDOMAIN)) || ((x + *pdx) < 0))
	{
		*pdx = random8() % 2 * (x < (XDOMAIN / 2) ? 1 : -1);
	}
	if (((y + *pdy) > (YDOMAIN)) || ((y + *pdy) < 0))
	{
		*pdy = random8() % 2 * (y < (YDOMAIN / 2) ? 1 : -1);
	}
	if (*pdx == 0 && *pdy == 0)
	{
		*pdx = (x < (XDOMAIN / 2) ? 1 : -1);
		*pdy = (y < (YDOMAIN / 2) ? 1 : -1);
	}
}

void laborlogo()
{
	uint16_t nCycles = FRAMECOUNT;
	int8_t x = random8() % (XDOMAIN + 1);
	int8_t y = random8() % (YDOMAIN + 1);
	int8_t dx = 0;
	int8_t dy = 0;

	while (nCycles-- != 0)
	{
		laborlogo_drawViewport(x ,y);
		laborlogo_recalcVectors(x, y, &dx, &dy);
		x += dx;
		y += dy;
		wait(FRAME_TICK);
	}
}