ChuChu Rocket-type game

Because you’re testing for the value of a BGMap cell, but to perform movement you’re moving the World itself (with GX and GY).

Other problems include:

1. Still using spaghetti code (goto label)
2. Reinitializing the VPU every time through the loop
3. Copying the Char/BGMap data to the VPU every time through the loop
4. Moving, then testing for collision, then moving again if collision detected

I would use a u8 array (or array of arrays) to store the levels and use the graphics data for what it is: graphics data.

Sounds like a good game to work on, though. Are you just going to translate the levels, try to make up your own, or both? What about coming up with new hazards/puzzle elements (its been forever since I played it, so I can’t suggest any :-P)

Looking forward to the finished product!

That looks a lot better (going a little heavy on the whitespace, but I can’t fault you for that).

It only takes a quick look in libgccvb.h and the wiki, but here is a quick run-down of vbSetWorld:

vbSetWorld(#, flags, GX, GP, GY, MX, MP, MY, W, H);

#: The World number to modify
flags: Visibility, BGMap number, Mode, etc.
GX: The horizontal position of the upper-left pixel of the World
GP: The parallax offset of the World
GY: The vertical position of the upper-left pixel of the World

MX: The horizontal position of the upper-left pixel of the source rectangle
MP: The parallax offset of the source rectangle
MY: The horizontal position of the upper-left pixel of the source rectangle

W: The width of the source rectangle, minus 1 (e.g. 383 for full-screen)
H: The height of the source rectangle, minus 1 (e.g. 223 for full-screen)

I found another problem: you’re not setting an end World. The first unused World should have the WRLD_END flag set, otherwise, every World will be drawn, wasting time and, on hardware, probably generating random garbage on screen.

I’m not sure about your terminology, but, if I understand you right, it’s actually a good idea to use different Worlds for different layers of the level (obstacles, “mice”, etc.).

What I was referring to in my first post was the practice of accessing the BGMap data to see what to collide with. It will be much more robust and “future-proof” if you use a map stored in a smaller format (like an array of unsigned chars) and use that for both collision testing and generating the BGMap data. Like so:

static const u8 level_one[16] = {
    1, 1, 1, 1,
    1, 0, 0, 1,
    1, 0, 0, 1,
    1, 1, 1, 1,
};

The real one will be much bigger, but you know what I’m getting at… You can also use an array of arrays, like so:

static const u8 level_one[4][4] = {
    { 1, 1, 1, 1 },
    { 1, 0, 0, 1 },
    { 1, 0, 0, 1 },
    { 1, 1, 1, 1 },
};

Also, that will not be sufficient for a complete level description. There will likely be some other data associated with a level. For that, you should use a struct. Any good C tutorial will help you with that.

Hope that helps!

Is it supposed to work in Reality Boy?

When I tried it I could move anywhere and also outside the box. Perhaps it doesn’t matter for now…

I could only place two blocks and it’s also possible to place them outside the box.

VirtualChris wrote:
Also, I had to use a goto statement in order to make this work. Can anyone tell me how to make it work without it?

Just put your “while(1)” loop contents in a loop with an exit condition and put that and the “level_start” code inside the “while(1)” loop–which should actually be a “for(;;)” loop, I’ve been told, since it skips the superfluous testing of 1 each time through. Here’s an example for the inner loop:

int keep_looping = -1;

while (keep_looping) {
.
.
.
    if () keep_looping = 0;
}

In that case, I’d put the inner loop inside a function that returns a different value depending on where the game should go next. You can then test the return value inside your main infinite loop:

void main() {

    int next_part = 0;
    int level_num = 0;

    initialize();

    for (;;) {

        switch (next_part) {
        case 0:
            next_part = start_level(level_num);
            break;

        case 1:
            next_part = level(level_num);
            break;

        case 2:
            level_num++;
            next_part = 1;
            break;
        }
    } // Loop until power-down

}

int initialize() {
    // Stuff you have before the while(1) loop
}

int start_level(int level_num) {
    // Stuff you have between level_start: and level_reset:
    return 1;
}

int level(int level_num) {
    for (;;) {

        // Stuff you have after level_reset: (except testing the map array instead of the BGMap!)

        if (win_condition) {
            return 3;
        } else {
            return 2;
        }
    }
}

You only need one block on the first level as well.

You should write something when you clear the second screen… 😉

I sent a PM.