/*******************************************************************************
 *	TvTestPattern	Simple TV test patern generator
 *			T.Barnaby,	BEAM Ltd,	27/11/04
 *******************************************************************************
 *
 * This code generates a simple interlaced test video.
 * The output format is 720x576 interlaced RGB (8,8,8 bits) raw data.
 * 
 */
#include <stdio.h>
#include <stdint.h>

typedef struct {
	uint8_t	red;
	uint8_t	green;
	uint8_t	blue;
} Pixel;

typedef struct {
	Pixel	data[576][720];
} Frame;



void generateInterlaceFrame(Frame* frame){
	int	x;
	int	y;
	int	n;
	int	overlap = 0;
		
	for(y = 0; y < 576/2; y++){
		if(y & 1){
			for(x = 0; x < 360 + overlap; x++){
				frame->data[y][x].red = 255;
			}
		}
		else {
			for(x = 360 - overlap; x < 720; x++){
				frame->data[y][x].green = 255;
			}
		}
	}
	
	for(y = 576/2; y < ((576*3)/4) + overlap; y++){
		for(x = 0; x < 720; x += 2){
			frame->data[y][x].red = 255;
		}
	}
	for(y = ((576*3)/4) - overlap; y < 576; y++){
		for(x = 0; x < 720; x += 2){
			frame->data[y][x+1].green = 255;
		}
	}
}

void clearArea(Frame* frame, int x, int y, int w, int h){
	int	ye = y + h;
	
	for(y = y; y < ye; y++){
		memset(&frame->data[y][x], 0, sizeof(Pixel) * w);
	}
}

void drawBox(Frame* frame, int x, int y, int w, int h){
	int	ye = y + h;
	
	for(y = y; y < ye; y++){
		memset(&frame->data[y][x], 0xFF, sizeof(Pixel) * w);
	}
}

void drawDiaganal(Frame* frame, int x, int y, int w, int h){
	int	xe = x + w;
	int	ye = y + h;
	Pixel	p;
	
	p.red = 255;
	p.green = 255;
	p.blue = 255;
	
	for(x = x; x < xe; x++, y++){
		frame->data[y][x] = p;
		frame->data[y][x+1] = p;
		frame->data[y][x+2] = p;
		frame->data[y][x+3] = p;
		frame->data[y][x+4] = p;
		frame->data[y][x+5] = p;
		frame->data[y][x+6] = p;
		frame->data[y][x+7] = p;
	}

}

void drawFrame(Frame* frame, int n){
	int	x = 100 + n % 500;
	
	clearArea(frame, 100, 100, 500, 300);
	drawBox(frame, x, 150, 10, 100);
	drawDiaganal(frame, 400, 100, 100, 100);
}

void mergeFrames(Frame* frame, Frame* frame1, Frame* frame2){
	int	x;
	int	y;
	
	for(y = 0; y < 576; y++){
		if(y & 1)
			memcpy(&frame->data[y][0], &frame2->data[y][0], sizeof(Pixel) * 720);
		else
			memcpy(&frame->data[y][0], &frame1->data[y][0], sizeof(Pixel) * 720);
	}
}

int main(int argc, char** argv){
	int		n;
//	int		num = 50*100;
	int		num = 50*40;
	Frame		frameEven;
	Frame		frameOdd;
	Frame		frame;
	int		enableEven = 1;
	int		enableOdd = 1;
	int		rev = 0;
	
	memset(&frameEven, 0, sizeof(frame));
	memset(&frameOdd, 0, sizeof(frame));
	if(enableEven){
		generateInterlaceFrame(&frameEven);
		clearArea(&frameEven, 100, 100, 500, 300);
	}
	
	if(enableOdd){
		generateInterlaceFrame(&frameOdd);
		clearArea(&frameOdd, 100, 100, 500, 300);
	}
	
	for(n = 0; n < num; n++){
		if((n & 1) == 0){
			if(enableEven)
				drawFrame(&frameEven, n);
		}
		else {
			if(enableOdd)
				drawFrame(&frameOdd, n);
			if(rev)
				mergeFrames(&frame, &frameEven, &frameOdd);
			else
				mergeFrames(&frame, &frameOdd, &frameEven);

			write(1, &frame, sizeof(frame));
		}
	}
	return 0;
}