This month's plug and play snippet is different; it shows several examples that make heavy use of the existing lite-C libraries. In fact, these libraries are perfect for the "plug and play" section of the magazine, because you only have to include them, and then you have access to a lot of pre-written code that will greatly simplify your job.
Copy the \pnplibs folder inside your Gamestudio folder, and then open and run pnplibs.c. I wanted to keep the code as simple as possible, so I didn't include a player action; this means that you will have to press the zero key once, and then use the arrow keys and Page Up / Page Down to move and look around.
Let's start with function main:
function main()
{
camera.ambient = 70;
fps_max = 70;
video_mode = 7; // run in 800x600 pixels
video_depth = 32; // 32 bit mode
video_screen = 1; // start in full screen mode
level_load (pnplibs_wmb);
wait (2);
ent_createlayer("skycube+6.tga", SKY | CUBE | SHOW, 1);
// splits an image file horizontally and vertically into several parts and stores them as separate files under the name "splitnm.bmp"
bmap_split("map.bmp", 2, 3); // split map.bmp into 2x3 = 6 smaller pieces, naming them split00.bmp... split21.bmp
}
This looks like a standard main( ) function, but take a look at the last line: it calls a bmap_split function which is located inside the bmap.c library and splits a bitmap into the desired number of pieces.
Don't forget to include bmap.c in your main script; otherwise, you won't have access to the functions inside it. Remember to do this for all the libraries that you plan to use.
Let's move on to a new library: entmove.c, a library that contains many entity-related functions. I chose to use a path patrolling function from within the library; take a look at the code and you'll see how easy it is to use.
action patroller()
{
var walk_percentage;
// let an entity move along the specified path, with a speed = 4, looking ahead
ent_movepath(my, "path_000", 4, 2);
while (1)
{
walk_percentage += 6 * time_step;
ent_animate(my, "walk", walk_percentage, ANM_CYCLE); // play the "walk" animation in a loop
wait (1);
}
}
Actually, the only line of code that is needed is this one:
ent_movepath(my, "path_000", 4, 2);
Yes, this line alone will move the entity on a path; the rest of the code was added by me because I wanted the guard model to be animated as well.
Moving on to a fresh library named mtlFX.c; it contains lots of shaders that can be tested by simply changing the name of the chosen material - here's a quick example.
action test_material()
{
my.material = mtl_specBump;
while (1)
{
my.pan += 2 * time_step;
wait (1);
}
}
The library comes with a great variety of materials: environment mapping, bump mapping, parallax mapping, chrome, glass, etc. Let's check out the particles.c library, which will speed up the process of creating particle effects significantly.
function snow_startup()
{
var number_of_flakes = 150; // sets the number of flakes
wait (-10); // wait for 10 seconds before starting the snow
while(1)
{
effect(p_snow, number_of_flakes * time_frame, vector(camera.x + 400 - random(800), camera.y + 400 - random(800), camera.z + 100), vector(-5, 2, 0));
wait(1);
}
}
I hope that you like my simple, and yet fully functional snow effect; it uses the p_snow library function that is included inside particles.c
The last example uses the strio.c library, which contains string and file-related functions.
STRING* temp_str = "This is a great way to replace words in a way that is way beyond imagination!";
function replace_startup()
{
while (!key_r) {wait (1);}
str_replaceall(temp_str, "way", "mode");
}
TEXT* string_txt =
{
pos_x = 20;
pos_y = 20;
string(temp_str);
flags = SHOW;
}
This time I am using the str_replaceall function, which replaces all the occurrences of the word "way" inside temp_str with "mode". Here's how the text looks like initially:
And here's the same string after a "R" key press which has run str_replaceall( ):
As you can see, all the code I've added is only used to make the things more user-friendly; the actual word replacement code consists of a single line. And I am sure that many of you would have been able to write functions like these ones, but why reinvent the wheel when there's no need to do that?
I couldn't cover all the functions from all the libraries here, but you are encouraged to do so: you can find them all inside Gamestudio's \include folder. I hope that by now you have realized the power that is hidden behind the existing lite-C libraries; I have to admit that I didn't use them too much until now, but this will definitely change from now on - I hope you'll do the same.