Thread: random music in C

Hey there.

I'm very very new to C and am having some trouble with a program I'm writing. The program is meant to improvise around a scale and do a different sequence everytime. However every time I start the program it does the exact same sequence despite it using random numbers.

Code:

#include "stdlib.h"
#include "midi_lib.h"
 
int main(void)
{

 /* Declare integer variables for specifying a note */
 int pitch, channel, velocity, offset, key;
 int i, bar_duration, note_duration;
 int velocity_reduction = 32;
    int program_quit=0;
    int scale_note;
 
   
    int major_scale[8] = {0, 2, 4, 5, 7, 9, 11, 12};
    int minor_scale[8] = {0, 2, 3, 5, 7, 8, 10, 12};
    int mixolydian_scale[8] = {0, 2, 4, 5, 7, 9, 10, 12};

 key = 60;  /* middle C */
 channel = 1;
 velocity = 64; /* mediu loudness */
 bar_duration = 4*400; /* the first four notes take this time */
    midi_start();

    while (!program_quit)
        {
            midi_note(key + mixolydian_scale[(rand() % (8+1-0))+0], 1, 64);
            pause((rand() % (500+1-125)) + 125);
            midi_note(key + mixolydian_scale[(rand() % (8+1-0))+0], 1, 0);
          
        }

    midi_close();
 return 0;
}

any help and advice would be much appreciated.

Cheers in advance

dogma93

awesome that worked thank you.

As a side question is there any way to make the note duration more musical? As it stands I've got it to play for a random amount of time but this is very inconsistant just sounds disordered.

Again any advice would be much appreciated

Cheers

that worked but it seems that the sample rate is off or something as the sound seems to stutter from time to time. The code also ocationalyl plays some chords and I don't know why.

Code:

  int note_held[4] = {1000, 750, 500, 250};
    midi_start();


 while (!program_quit)
        {
            midi_note(key + mixolydian_scale[(rand() % (8+1-0))+0], 65, ((rand() % (124+1-64))+64));
            pause(note_held[((rand() % (4+1-0)) + 0)]);
            midi_note(key + mixolydian_scale[(rand() % (8+1-0))+0], 65, 0);
            srand (time(NULL));
        }

srand should only be called once, at the start of your program, never inside a loop.

Hey there I'm trying to use switch statements in my code so that the key can be changed in real time using keyboard presses. However when I use a while loop around the switch statements nothing happens at all. Any ideas on what I've done wrong?

Code:

 int letter_entered;

letter_entered = getch();

while(!program_quit)
{
    switch (letter_entered)
    {
        case 'a': case 'A':
        key = 57;
        break;
        case 'b': case 'B':
        key = 59;
        break;
        case 'v': case 'V':
        key = 58;
        break;
        case 'h': case 'H':
        key = 56;
        break;
        case 'g': case 'G':
        key = 55;
        break;
        case 't': case 'T':
        key = 54;
        break;
        case 'f': case 'F':
        key = 53;
        break;
        case 'e': case 'E':
        key = 52;
        break;
        case 'w': case 'W':
        key = 51;
        break;
        case 'd': case 'D':
        key = 50;
        break;
        case 's': case 'S':
        key = 51;
        break;
        case 'c': case 'C':
        key = 60;
        break;
        default:
        printf ("that was an invalid input");
        break;
    }
}