Animation problem? - c++

Question

Right now when i start my game am making in C++ i walk left right up or down.. But the character just slides doesn't look like he's walking.. And i have all the pictures already loaded into my game and they are working.. But i don't know how i would solve it.. Thing i can't figure out is how to make the picture change when u hold the button..
This is in allegro by the way..
Here is my code for the drawing player:
void Player::Draw(BITMAP *Buffer){
draw_sprite(Buffer, Oskar[picNumber], x, y);
}
Oskar[] is the name of the Array with all the pictures..
Here is what changes the picture for the character when u press the buttons:
void Player::Controls(){
if(key[KEY_RIGHT]){
velocityX = speed;
picNumber = 6;
}
else if(key [KEY_LEFT]){
velocityX = -speed;
picNumber = 9;
}
else{
velocityX = 0;
}
if(key [KEY_UP]){
velocityY = -speed;
picNumber = 3;
}
else if(key [KEY_DOWN]){
velocityY = speed;
picNumber = 0;
}
else{
velocityY = 0;
}
x += velocityX;
y += velocityY;
}
Its all about the variable i created picNumber.. All pictures i have is in an Array and the picNumber is represents what picture to be drawn..
Would be nice to get some help on this.. I've been thinking all day about this..
EDIT
#include "Player.h"
#include "Global.h"
#include <allegro.h>
Player::Player(){
}
Player::~Player(){
}
void Player::Init(){
x = 10;
y = 10;
velocityX = 0;
velocityY = 0;
speed = 1;
picNumber = x % MAXPICS;
OskarFront[0] = load_bitmap("Character\\OskarFront.bmp", NULL);
OskarFront[1] = load_bitmap("Character\\OskarStanding.bmp", NULL);
OskarFront[2] = load_bitmap("Character\\OskarFront2.bmp", NULL);
OskarBack[0] = load_bitmap("Character\\OskarBack.bmp", NULL);
OskarBack[1] = load_bitmap("Character\\OskarStandingBack.bmp", NULL);
OskarBack[2] = load_bitmap("Character\\OskarBack2.bmp", NULL);
OskarRight[0] = load_bitmap("Character\\Oskar1.bmp", NULL);
OskarRight[1] = load_bitmap("Character\\Oskar.bmp", NULL);
OskarRight[2] = load_bitmap("Character\\Oskar2.bmp", NULL);
OskarLeft[0] = load_bitmap("Character\\OskarLeft.bmp", NULL);
OskarLeft[1] = load_bitmap("Character\\OskarLeftStand.bmp", NULL);
OskarLeft[2] = load_bitmap("Character\\OskarLeft2.bmp", NULL);
}
void Player::Update(){
Player::Controls();
}
void Player::Draw(BITMAP *Buffer){
if(walkingRight == true){
draw_sprite(Buffer, OskarRight[picNumber], x, y);
}
else if(walkingLeft == true){
draw_sprite(Buffer, OskarLeft[picNumber], x, y);
}
else if(walkingFront == true){
draw_sprite(Buffer, OskarFront[picNumber], x, y);
}
else if(walkingBack == true){
draw_sprite(Buffer, OskarBack[picNumber], x, y);
}
else{
draw_sprite(Buffer, OskarFront[1], x, y);
}
}
void Player::Controls(){
if(key[KEY_RIGHT]){
velocityX = speed;
walkingRight = true;
}
else if(key [KEY_LEFT]){
velocityX = -speed;
walkingLeft = true;
}
else{
walkingRight = false;
walkingLeft = false;
velocityX = 0;
}
if(key [KEY_UP]){
velocityY = -speed;
walkingFront = true;
}
else if(key [KEY_DOWN]){
velocityY = speed;
walkingBack = true;
}
else{
velocityY = 0;
walkingFront = false;
walkingBack = false;
}
x += velocityX;
y += velocityY;
}
here is now the new full code i typed after getting help here.. Its now not working when am walking up its showing the front picture and am walking down the up picture is showing.. But left and right works.. Also its not changing picture like animation..

Answer 1

You only have one index for each direction of movement!
Assuming you have drawn about 3 (left leg forward, overlap, right leg forward) you would need to increment the index with time or movement as the march progresses.
Interesting how far Allegro has progressed- a decade ago it was mainly DOS graphics (I used it with DJGPP) and had a note from the author living in a London flat. How austere I thought, only now do I see how far off of London prices we provincials are.
In answer to your comment, try something like:
#define MAXPICS 3
BITMAP *OskarWalksLeft[MAXPICS];
BITMAP *OskarWalksRight[MAXPICS];
picNumber = x % MAXPICS;
if (facingLeft) {
draw_sprite(Buffer, OskarWalksLeft[picNumber], x, y);
} else //facingRight
draw_sprite(Buffer, OskarWalksRight[picNumber], x, y);
or if you don't want a new frame per pixel but every 3 or so try replacing
picNumber = x % MAXPICS;
with
picNumber = (x / 3) % MAXPICS;
I've tried tidying up your code a little and come up with this, I don't have allegro so couldn't test it:
#include "Player.h"
#include "Global.h"
#include <allegro.h>
Player::Player(){}
Player::~Player(){}
enum playerDir {left, right, front, back, stationary} direction;
BITMAP *Oskar[stationary][3];
void Player::Init(){
x = 10;
y = 10;
velocityX = 0;
velocityY = 0;
speed = 1;
picNumber = x % MAXPICS;
char filename[256];
const char *dirStrs[] = {"left","right","front","back"};
for (playerDir i = left; i < stationary; (int)i = (int)i + 1)
for (j = 0; j < 3; ++j) {
strcpy(filename, "Character\\Oskar");
strcat(filename, dirStrs[i]);
strcat(filename, itoa(j));
strcat(filename, ".bmp");
Oskar[i][j] = load_bitmap(filename, NULL);
}
}
void Player::Update(){Player::Controls();}
void Player::Draw(BITMAP *Buffer){
switch (direction) {
case left :
draw_sprite(Buffer, OskarLeft[picNumber], x, y);
break;
case right :
draw_sprite(Buffer, OskarRight[picNumber], x, y);
break;
case front :
draw_sprite(Buffer, OskarFront[picNumber], x, y);
break;
case back :
draw_sprite(Buffer, OskarBack[picNumber], x, y);
break;
default:
draw_sprite(Buffer, OskarFront[1], x, y);
}
}
void Player::Controls(){
direction = stationary;
if(key[KEY_RIGHT]){
velocityX = speed;
direction = right;
} else if(key [KEY_LEFT]){
velocityX = -speed;
direction = left;
} else velocityX = 0;
if(key [KEY_UP]){
velocityY = -speed;
direction = front;
} else if(key [KEY_DOWN]){
velocityY = speed;
direction = back;
} else velocityY = 0;
x += velocityX;
y += velocityY;
}

Answer 2

You don't seem to be doing any animation. It seems you are just setting a specific frame based on the direction key the user is pressing. You need a function that does something like this:
void Player::updateFrame(float time_delta)
{
time_to_next_frame -= time_delta;
while (time_to_next_frame <= 0.0f)
{
nextFrame();
time_to_next_frame += time_per_frame;
}
}
Call it every frame, passing it the amount of time that has elapsed since the last frame.

Answer 3

In response to your comments on the other 2 answers, you seem to be unsure of how to not go over a specific value.
To do this (for instance you want something in the range [0, 2] + c, where c is some constant determining the start of your index. So for instance, you could do the following:
void Player::nextFrame( int startIndex /* Changes based on your direction */) {
static unsigned short iIndex = 0;
// Increment and map value to the range [0, 2]
++iIndex;
iIndex %= 3;
// Note: this assumes that picNumber is a member function, else you
// will have to pass it by reference to this function.
picNumber = iIndex + startIndex;
}
This should do what you want (i.e. depending on the direction you change the start index to suit, and then it increments, mapping the value to the range [0, 2].
Hope this helps!