/* This Applet was created by Michael Morton for use by the Math Forum. You may use pieces of code only with the consent of the Math Forum. */ /* This is the Canvas for the Traffic Jam Applet. It draws the images, handles the movements thereof, and the counter/goal_strings. */ import java.awt.*; public class JamCan extends Panel { // Setup Control Ints final int NUM_ROWS = 1, PIC_WIDTH = 34, PIC_HEIGHT = 52, NUM_TOTAL = 9, NUM_COLS = 9, GAP = 0, STR_GAP = 0, X_INSET = 50, Y_INSET = 10, XTOP=125, YTOP=35; // lowest = lowest possible moves for this level int curr_cols = 7, temp, jam_level = 2, lowest=15; Image all_pics[] = new Image[NUM_TOTAL]; // pics_order keeps track of the current order of the pics int pics_order[] = {0, 1, 2, 3, 4, 5, 6, 7, 8}; // goal_order keeps track of the goal order for the current level int goal_order[] = {0, 5, 6, 7, 4, 1, 2, 3, 8}; int xpos, ypos, blank=4, counter=0, counter_x, counter_y, change=0; // box[][] keeps track of where each image can be moved (drawn) int box[][] = new int[NUM_TOTAL][4]; Color fgjamcolor=Color.white,bgjamcolor=Color.black; Font all_font,top_font; Jam outerparent; JamCan(Jam target, Image all_da_pics[]) { // Copy over the pics so globally availably here for(int i = 0; i < NUM_TOTAL; i++) all_pics[i] = all_da_pics[i]; // So can contact parent this.outerparent = target; // Set Font all_font = new Font("TimesRoman", Font.PLAIN, 20); top_font = new Font("TimesRoman", Font.BOLD, 30); // Set Background setBackground(bgjamcolor); //Setup where the counter: # will be printed on the Frame counter_x = X_INSET; counter_y = (NUM_ROWS * (PIC_HEIGHT+GAP)) + Y_INSET+YTOP + 30; // This box[][] contains info about where each 'person' is printed // on the screen. The first [] are the 9 places where could possibly // be printing a 'person'. The second [] contains 4 ints. They are: // top-left corner x and y position, x-width and y-height. This // information is mostly used when you click to find out which // 'person' you clicked on. for (int i = 0; i < NUM_TOTAL; i++) { box[i][0] = (int)(X_INSET + (GAP + PIC_WIDTH) * (i % NUM_COLS)); // X-POS box[i][1] = (int)(Y_INSET + YTOP + (GAP + PIC_HEIGHT) * Math.floor(i / NUM_COLS)); // Y-POS box[i][2] = box[i][0] + PIC_WIDTH; // X-WIDTH box[i][3] = box[i][1] + PIC_HEIGHT; // Y-HEIGHT } } // This handles the clicking. It takes as arguments where you click. // It first runs through the shown 'people' (using jam_level); using // the boxes[][] it can quickly check if you did indeed click on a 'person' public boolean mouseDown(Event evt, int x, int y) { for (int i = 3-jam_level; i <= 5+jam_level; i++) { if (x > box[i][0] && x < box[i][2] && y > box[i][1] && y < box[i][3]) { // Depending on which 'person' is clicked on, it checks to see if it's // a legal move. If it is, it switches the two 'people, adds to // the counter, and re-draws. if (is_legal(i)){ temp = pics_order[i]; pics_order[i] = pics_order[blank]; pics_order[blank] = temp; outerparent.history.change(i,blank); blank = i; counter++; repaint(); } } } return true; } // Over-ride main update so that it only re-draws the 'people' not // background (no flicker then). But, if there is a change in the level // (i.e. reset everything), need to re-draw the background. thus, the // change variable. public void update(Graphics g) { if(change == 1) { setBackground(bgjamcolor); g.setColor(bgjamcolor); g.fillRect(0,0,size().width,size().height); change = 0; } paint(g); } public void paint (Graphics g) { String counter_string = "Counter: " + counter; String finish_string = "You got it!"; String top_string = "Traffic Jam!"; String best_string = "Completed in the Least Number of Moves!"; String tryagain_string = "Good job. Try again to complete in less moves."; FontMetrics fm = getFontMetrics(all_font); String this_string; int str_y; // Draw the topString g.setColor(fgjamcolor); g.setFont(top_font); g.drawString(top_string,XTOP,YTOP); // Draw the pics in the correct order. (and draw the correct // number of them (for the level). for (int j = 3-jam_level; j <= 5+jam_level; j++) { if(pics_order[j] == 4) { g.setColor(bgjamcolor); g.fillRect(box[j][0],box[j][1], PIC_WIDTH, PIC_HEIGHT); } else g.drawImage(all_pics[pics_order[j]], box[j][0], box[j][1], this); } // Draw Counter. Draw a rectangle in background color // over old number, put up the new number. g.setFont(all_font); g.setColor(bgjamcolor); g.fillRect(counter_x + fm.stringWidth("Counter: "), counter_y - fm.getAscent(), fm.stringWidth("9999"), fm.getHeight()); g.setColor(fgjamcolor); g.drawString(counter_string, counter_x, counter_y); // Draw Finish. Draw a rectangle in the background color. str_y = counter_y + fm.getHeight() + STR_GAP; g.setColor(bgjamcolor); g.fillRect(counter_x, str_y - fm.getAscent(), fm.stringWidth(finish_string), fm.getHeight()); g.setColor(fgjamcolor); if (goal_state()) // If goal is true, draw the Win String. g.drawString(finish_string, counter_x, str_y); // Draw Win/Try again. if (counter == lowest) this_string = best_string; else this_string = tryagain_string; str_y = str_y + fm.getHeight() + STR_GAP; g.setColor(bgjamcolor); g.fillRect(counter_x, str_y - fm.getAscent(), fm.stringWidth(this_string), fm.getHeight()); g.setColor(fgjamcolor); if (goal_state()) g.drawString(this_string, counter_x, str_y); } // This function is called when click on a level to reset and start // at that level. void update_level(int level) { for(int i = 0;i < NUM_TOTAL;i++) pics_order[i] = i; // Reset the pics order // to starting order. // These set up the goal order. this is funky b/c if the level // is not the hardest, some pics never get moved (at the ends) // and so, kinda funky order of numbers. if(level == 1) { goal_order[0] = 0;goal_order[1] = 1;goal_order[2] = 5; goal_order[3] = 6;goal_order[4] = 4;goal_order[5] = 2; goal_order[6] = 3;goal_order[7] = 7;goal_order[8] = 8; lowest = 8; } else if(level == 2) { goal_order[0] = 0;goal_order[1] = 5;goal_order[2] = 6; goal_order[3] = 7;goal_order[4] = 4;goal_order[5] = 1; goal_order[6] = 2;goal_order[7] = 3;goal_order[8] = 8; lowest = 15; } else if(level == 3) { goal_order[0] = 5;goal_order[1] = 6;goal_order[2] = 7; goal_order[3] = 8;goal_order[4] = 4;goal_order[5] = 0; goal_order[6] = 1;goal_order[7] = 2;goal_order[8] = 3; lowest = 24; } // Reset the variables. jam_level = level; change = 1; // Set to 1 so that it re-draws the Frame curr_cols = 3+2*level; counter = 0; blank = 4; repaint(); } // This changes the Foreground or Background Color variable, and // re-draws the Frame void updatecolor(String choice, Color col) { if(choice.equals("fg")) fgjamcolor = col; else if(choice.equals("bg")) { bgjamcolor = col; change = 1; } repaint(); } // This checks if the pics_order is the same as the goal_order. // If it is, it return True. public boolean goal_state() { boolean ret; for (int i = 0; i < curr_cols; i++) { if (pics_order[i] == goal_order[i]) ; else return false; } return true; } // This checks to see if it's a legal move. Return True if it is. public boolean is_legal (int i) { boolean ret=false; if (blank == (i+1) || blank == (i-1)) // If blank is on ret = true; // either side: True. // If the blank is one space away (+-2) and the one b/w is an // opposite 'person': True. else if ((blank == (i+2) && is_opposite(i,i+1)) || (blank == (i-2) && is_opposite(i,i-1))) ret = true; return ret; } // Checks to see if the two 'people' are opposites. public boolean is_opposite(int i, int j) { boolean ret = false; if(Math.abs(pics_order[i] - pics_order[j]) > 1) ret = true; return ret; } }