Scroller2.c

#include "Epileptor.h"
#include "Global.h"
#include "VGA.h"
#include "LED.h"
#include "Button.h"
#include "Utils.h"
#include "Random.h"

#include "Graphics/Bitmap.h"
#include "Graphics/Drawing.h"
#include "Graphics/Font.h"

#include <stdint.h>
#include <string.h>

static uint32_t sqrti(uint32_t n);

extern Font OLFont;

void Scroller2(const char *message)
{
	uint8_t *framebuffer1=(uint8_t *)0x20000000;
	uint8_t *framebuffer2=(uint8_t *)0x20010000;
	memset(framebuffer1,0,320*200);
	memset(framebuffer2,0,320*200);
	
	for(int32_t c = 0; c < 8; c++) {
		data.scroller2.barTable[0][c] = RawRGB(c,0,c/2);
		data.scroller2.barTable[1][c] = RawRGB(0,c,c/2);
		data.scroller2.barTable[2][c] = RawRGB(c,c,c/2);
		data.scroller2.barTable[0][15 - c] = RawRGB(c,0,c/2);
		data.scroller2.barTable[1][15 - c] = RawRGB(0,c,c/2);
		data.scroller2.barTable[2][15 - c] = RawRGB(c,c,c/2);
	}

	SetVGAScreenMode320x200(framebuffer1);

	Bitmap frame1,frame2;
	InitializeBitmap(&frame1,320,200,320,framebuffer1);
	InitializeBitmap(&frame2,320,200,320,framebuffer2);

	int frame=0;
	int first=VGAFrameCounter();
	
	while(CurrentBitBinRow(&song) < 768)
	{
		WaitVBL();

		Bitmap *currframe;
		if(frame)
		{
			currframe=&frame2;
			SetFrameBuffer(framebuffer1);
		}
		else
		{
			currframe=&frame1;
			SetFrameBuffer(framebuffer2);
		}
		ClearBitmap(currframe);

		uint8_t* pixels = currframe->pixels;
		
		int t=VGAFrameCounter()-first;
		int x=320-t*3;

		SeedRandom(CurrentBitBinRow(&song)>>3);
		for(int ya = 0; ya < 200; ya += 20 ) {
			for(int xa = 0; xa < 320; xa += 20 ) {
				int val = (RandomInteger() + (t>>2)) % 48;
				uint8_t col = data.scroller2.barTable[0][val];
				for(int y = 1; y < 19; y++ ) {
					for(int x = 1; x < 19; x++ ) {
						pixels[xa+x+(ya+y)*320] = col;
					}
				}
			}
		}
		
		for(int i = 0; i < 3; i++ ) {
			for(int l = 0; l < 16; l++) {
				if(icos((i * 4096)/3+t*33)>0) {
					DrawHorizontalLine(currframe, 0, (isin((i * 4096)/3+t*33)>>7)+100-8+l, 320, data.scroller2.barTable[i][l]);
				}
			}
		}

		for(const char *ptr=message;*ptr;ptr++)
		{
			int c=*ptr;

			int y=(isin(x*20+t*33)>>9)+100-8;

			DrawCharacter(currframe,&OLFont,x,y,0,c);

			x+=WidthOfCharacter(&OLFont,c)+2;
		}

		for(int i = 0; i < 3; i++ ) {
			for(int l = 0; l < 16; l++) {
				if(icos((i * 4096)/3+t*33)<=0) {
					DrawHorizontalLine(currframe, 0, (isin((i * 4096)/3+t*33)>>7)+100-8+l, 320, data.scroller2.barTable[i][l]);
				}
			}
		}

		SetLEDs(1<<((t/3)&3));

		frame^=1;
	}


// 	while(UserButtonState());
}

static uint32_t sqrti(uint32_t n)
{
	uint32_t s,t;

	#define sqrtBit(k) \
	t = s+(1UL<<(k-1)); t <<= k+1; if (n >= t) { n -= t; s |= 1UL<<k; }

	s=0;
	if(n>=1<<30) { n-=1<<30; s=1<<15; }
	sqrtBit(14); sqrtBit(13); sqrtBit(12); sqrtBit(11); sqrtBit(10);
	sqrtBit(9); sqrtBit(8); sqrtBit(7); sqrtBit(6); sqrtBit(5);
	sqrtBit(4); sqrtBit(3); sqrtBit(2); sqrtBit(1);
	if(n>s<<1) s|=1;

	#undef sqrtBit

	return s;
}