<SCRIPT type="text/javascript"> // ---- Make array function MakeArray( n){ this.length = n; for (var i = 1; i <= n; i++) { this[i] = 0 } return this } // ----- poor man's random number var d0 = new Date(); var r0 = d0.getSeconds(); function poor_rand(){ d1 = new Date(); r0 = (r0 * r0 + r0 + d1.getSeconds()) % 3721 ; return r0 % width_n; } // ---- Parameters of game var height_n = 8; var width_n =5; // ---- state of game var enemy = new MakeArray( width_n); // enemy positions var wtime; // wait time var score; // points var gameover; // in case of gameover set to true // ----- Make the battlefield. document.write( "<FORM NAME='fm1'>"); document.write( "<INPUT TYPE='text' NAME='message' SIZE=20>"); document.write( "</FORM>"); document.write( "<FORM NAME='fm2'><TABLE>"); for( var i=0; i<height_n; i++){ document.write( "<TR>"); for( var j=0;j<width_n; j++){ document.write( "<TD><CENTER><INPUT TYPE='radio'></CENTER></TD>"); } document.write( "</TR>"); } document.write( "<TR>"); for( var j=0;j<width_n; j++){ document.write( "<TD><INPUT TYPE='button' VALUE='-x-' onClick='fire(" + j + ")'></TD>"); } document.write( "</TR>"); document.write( "</TABLE>"); document.write( "<INPUT TYPE='button' VALUE='START' onClick='game_start()'>"); document.write( "</FORM>"); // ----- game main timer event // ----- enemy come one step function come(){ var n = poor_rand(); document.fm2.elements[ width_n * enemy[n+1] + n].checked = true; enemy[n+1]++; if( enemy[n+1] < height_n){ setTimeout("come()", wtime); }else{ gameover = true; document.fm1.message.value = "GAME OVER:" + score ; } } // ----- Fire the n th beam function fire( n){ if( gameover ) return; for( var i=0; i<enemy[n+1]; i++){ // clear enemy document.fm2.elements[ width_n * i + n].checked = false; } score += enemy[ n+1]; document.fm1.message.value = "Points:" + score; enemy[ n+1] = 0; if( wtime > 100){ wtime -= 10}; } // ---- initialize & start game function game_start(){ for( var n=0; n<width_n; n++){ for( var i=0; i<enemy[n+1]; i++){ document.fm2.elements[ width_n * i + n].checked = false; } enemy[n+1] = 0; } wtime = 400; score = 0; gameover = false; document.fm1.message.value = "Points:" + score; setTimeout("come()", wtime); } // --> </SCRIPT>