Video tearing left to right

I bought the shield from you just recently and got it in the mail today. Fine piece of work.

I tried the VE sketch for the NTSCDemo (within the TVout-VE library) and the text and graphics are tearing left to right like crazy. Then I tried your Video Overlay demo with the randomized up and down graph and the scrolling letters, and it worked fine, as did the Object Tracking code and the edge detection sketch.

Could it be the Arduino Uno R3 causing issues? Why is this tearing happening in the NTSC Demo that the library comes with, is it just that the demo wasn’t modified with the rest of the library to be optimized for the VE? Is there something in the NTSC demo that can be modified to work well with the VE?

Here’s the code for the NTSCDemo:

#include 

#include 

#include "schematic.h"

#include "TVOlogo.h"



TVout TV;



int zOff = 150;

int xOff = 0;

int yOff = 0;

int cSize = 50;

int view_plane = 64;

float angle = PI/60;



float cube3d[8][3] = {

{xOff - cSize,yOff + cSize,zOff - cSize},

{xOff + cSize,yOff + cSize,zOff - cSize},

{xOff - cSize,yOff - cSize,zOff - cSize},

{xOff + cSize,yOff - cSize,zOff - cSize},

{xOff - cSize,yOff + cSize,zOff + cSize},

{xOff + cSize,yOff + cSize,zOff + cSize},

{xOff - cSize,yOff - cSize,zOff + cSize},

{xOff + cSize,yOff - cSize,zOff + cSize}

};

unsigned char cube2d[8][2];





void setup() {

TV.begin(NTSC,120,96);

TV.select_font(font6x8);

intro();

TV.println("I am the TVoutnlibrary running on a freeduinon");

TV.delay(2500);

TV.println("I generate a PALnor NTSC composite  video usingninterruptsn");

TV.delay(2500);

TV.println("My schematic:");

TV.delay(1500);

TV.bitmap(0,0,schematic);

TV.delay(10000);

TV.clear_screen();

TV.println("Lets see whatnwhat I can do");

TV.delay(2000);



//fonts

TV.clear_screen();

TV.println(0,0,"Multiple fonts:");

TV.select_font(font4x6);

TV.println("4x6 font FONT");

TV.select_font(font6x8);

TV.println("6x8 font FONT");

TV.select_font(font8x8);

TV.println("8x8 font FONT");

TV.select_font(font6x8);

TV.delay(2000);



TV.clear_screen();

TV.print(9,44,"Draw Basic Shapes");

TV.delay(2000);



//circles

TV.clear_screen();

TV.draw_circle(TV.hres()/2,TV.vres()/2,TV.vres()/3,WHITE);

TV.delay(500);

TV.draw_circle(TV.hres()/2,TV.vres()/2,TV.vres()/2,WHITE,INVERT);

TV.delay(2000);



//rectangles and lines

TV.clear_screen();

TV.draw_rect(20,20,80,56,WHITE);

TV.delay(500);

TV.draw_rect(10,10,100,76,WHITE,INVERT);

TV.delay(500);

TV.draw_line(60,20,60,76,INVERT);

TV.draw_line(20,48,100,48,INVERT);

TV.delay(500);

TV.draw_line(10,10,110,86,INVERT);

TV.draw_line(10,86,110,10,INVERT);

TV.delay(2000);



//random cube forever.

TV.clear_screen();

TV.print(16,40,"Random Cube");

TV.print(28,48,"Rotation");

TV.delay(2000);



randomSeed(analogRead(0));

}



void loop() {

int rsteps = random(10,60);

switch(random(6)) {

case 0:

for (int i = 0; i < rsteps; i++) {

zrotate(angle);

printcube();

}

break;

case 1:

for (int i = 0; i < rsteps; i++) {

zrotate(2*PI - angle);

printcube();

}

break;

case 2:

for (int i = 0; i < rsteps; i++) {

xrotate(angle);

printcube();

}

break;

case 3:

for (int i = 0; i < rsteps; i++) {

xrotate(2*PI - angle);

printcube();

}

break;

case 4:

for (int i = 0; i < rsteps; i++) {

yrotate(angle);

printcube();

}

break;

case 5:

for (int i = 0; i < rsteps; i++) {

yrotate(2*PI - angle);

printcube();

}

break;

}

}



void intro() {

unsigned char w,l,wb;

int index;

w = pgm_read_byte(TVOlogo);

l = pgm_read_byte(TVOlogo+1);

if (w&7)

wb = w/8 + 1;

else

wb = w/8;

index = wb*(l-1) + 2;

for ( unsigned char i = 1; i < l; i++ ) {

TV.bitmap((TV.hres() - w)/2,0,TVOlogo,index,w,i);

index-= wb;

TV.delay(50);

}

for (unsigned char i = 0; i < (TV.vres() - l)/2; i++) {

TV.bitmap((TV.hres() - w)/2,i,TVOlogo);

TV.delay(50);

}

TV.delay(3000);

TV.clear_screen();

}



void printcube() {

//calculate 2d points

for(byte i = 0; i < 8; i++) {

cube2d[0] = (unsigned char)((cube3d[0] * view_plane / cube3d[2]) + (TV.hres()/2));

cube2d[1] = (unsigned char)((cube3d[1] * view_plane / cube3d[2]) + (TV.vres()/2));

}

TV.delay_frame(1);

TV.clear_screen();

draw_cube();

}



void zrotate(float q) {

float tx,ty,temp;

for(byte i = 0; i < 8; i++) {

tx = cube3d[0] - xOff;

ty = cube3d[1] - yOff;

temp = tx * cos(q) - ty * sin(q);

ty = tx * sin(q) + ty * cos(q);

tx = temp;

cube3d[0] = tx + xOff;

cube3d[1] = ty + yOff;

}

}



void yrotate(float q) {

float tx,tz,temp;

for(byte i = 0; i < 8; i++) {

tx = cube3d[0] - xOff;

tz = cube3d[2] - zOff;

temp = tz * cos(q) - tx * sin(q);

tx = tz * sin(q) + tx * cos(q);

tz = temp;

cube3d[0] = tx + xOff;

cube3d[2] = tz + zOff;

}

}



void xrotate(float q) {

float ty,tz,temp;

for(byte i = 0; i < 8; i++) {

ty = cube3d[1] - yOff;

tz = cube3d[2] - zOff;

temp = ty * cos(q) - tz * sin(q);

tz = ty * sin(q) + tz * cos(q);

ty = temp;

cube3d[1] = ty + yOff;

cube3d[2] = tz + zOff;

}

}



void draw_cube() {

TV.draw_line(cube2d[0][0],cube2d[0][1],cube2d[1][0],cube2d[1][1],WHITE);

TV.draw_line(cube2d[0][0],cube2d[0][1],cube2d[2][0],cube2d[2][1],WHITE);

TV.draw_line(cube2d[0][0],cube2d[0][1],cube2d[4][0],cube2d[4][1],WHITE);

TV.draw_line(cube2d[1][0],cube2d[1][1],cube2d[5][0],cube2d[5][1],WHITE);

TV.draw_line(cube2d[1][0],cube2d[1][1],cube2d[3][0],cube2d[3][1],WHITE);

TV.draw_line(cube2d[2][0],cube2d[2][1],cube2d[6][0],cube2d[6][1],WHITE);

TV.draw_line(cube2d[2][0],cube2d[2][1],cube2d[3][0],cube2d[3][1],WHITE);

TV.draw_line(cube2d[4][0],cube2d[4][1],cube2d[6][0],cube2d[6][1],WHITE);

TV.draw_line(cube2d[4][0],cube2d[4][1],cube2d[5][0],cube2d[5][1],WHITE);

TV.draw_line(cube2d[7][0],cube2d[7][1],cube2d[6][0],cube2d[6][1],WHITE);

TV.draw_line(cube2d[7][0],cube2d[7][1],cube2d[3][0],cube2d[3][1],WHITE);

TV.draw_line(cube2d[7][0],cube2d[7][1],cube2d[5][0],cube2d[5][1],WHITE);

}