Matrix Command

Makefile

@@ -132,7 +132,8 @@ UPROGS=\
 	$U/_grind\
 	$U/_wc\
 	$U/_zombie\
-
+	$U/_matrix\
+
 fs.img: mkfs/mkfs README.md $(UPROGS)
 	mkfs/mkfs fs.img README.md $(UPROGS)
 

user/matrix.c

@@ -0,0 +1,114 @@
+#include "kernel/types.h"
+#include "kernel/stat.h"
+#include "user/user.h"
+
+// CITATION : CHATGPT walked us through how to do custom random num generator since we cant use rand()
+// random num generator to maintain curr seed for the RNG
+unsigned int seed = 12345678;
+
+//linear congruential generator algorithm to generate random number 
+// CITATION: got code from https://stackoverflow.com/questions/24494611/linear-congruential-generator-c
+//method to generate random number bc we can't use rand()
+unsigned int rand_lcg() {
+    seed = (1103515245 * seed + 12345) & 0x7fffffff;
+    return seed;
+}
+
+//return a random number from 0 to "max" using the rand-lcg function
+unsigned int rand_range(int max) {
+    return rand_lcg() % max;
+}
+
+// function to clear the screen using ANSI escape code
+void clear_screen() {
+    printf("\033[H\033[J");
+}
+
+// Function to generate matrix rain effect
+void matrix_effect(int rows, int cols, int max_iter, const char *color, int rainbow) {
+        // characters used in the matrix rain effect
+    char charset[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()";
+    // len  of the charset arr /wo null termminator  used to select random characters
+    int charset_len = sizeof(charset) - 1;
+
+    // color array for rainbow flag
+    const char* colors[] = {
+        "\033[31m", // red
+        "\033[33m", // y3llow :>
+        "\033[32m", // green
+        "\033[34m", // blue
+        "\033[35m", // magenta
+        "\033[36m", // cyan
+    };
+
+    int num_colors = sizeof(colors) / sizeof(colors[0]); //calculates number of colors in color array for later use
+    int iteration = 0; // counter for how long the effect will run
+    int column_pos[cols];  // track positions for each column's falling chars
+
+    // initialize each column to a random starting row
+    for (int j = 0; j < cols; j++) {
+        column_pos[j] = rand_range(rows);
+    }
+    // loop to run the effect for the duration (set iteration of 2)
+    while (iteration < max_iter) {
+        //for each column and row in matrix: 
+        for (int i = 0; i < rows; i++) {
+            for (int j = 0; j < cols; j++) {
+            	// check if rainbow flag is 1 and get color accordingly
+            	const char* current_color;
+            	if (rainbow) {
+            		//sets current_color to one of the colors in the array so that it changes each time
+            	    current_color = colors[j % num_colors];
+            	} else {
+            		//sets current_color to the flaged color
+            	    current_color = color;
+            	}
+                //make sure row and col are equal in order to print
+                if (i == column_pos[j]) {
+                    //get random number to print
+                    char ch = charset[rand_range(charset_len)];
+                    printf("%s%c\033[0m", current_color, ch);
+                    //print char in a diff postiion to stagger output
+                } else if (rand_range(10) < 2) {
+                    printf("%s%c\033[0m", current_color, charset[rand_range(charset_len)]);
+                } else {
+                //if all else fails just print a space
+                    printf(" ");
+                }
+            }
+            printf("\n");  // new line after each row
+        }
+        //update the position of the falling code
+        for (int j = 0; j < cols; j++) {
+            column_pos[j] = (column_pos[j] + 1) % rows;
+        }
+        iteration += 1;  //increment iteration
+    }
+
+}
+
+int main(int argc, char *argv[]) {
+    int rows = 24; // 80 by 24 for columns and rows to fit basic terminal size
+    int cols = 80;
+    int max_iter = 5;  // most amount of iterations
+    int rainbow = 0;  // flag for rainbow effect
+
+    const char *color = "\033[32m";  // default green color
+    // conditional for checking flags
+    if (argc > 1) {
+        if (strcmp(argv[1], "-pink") == 0) {
+            color = "\033[95m";  // pink 
+        } else if (strcmp(argv[1], "-blue") == 0) {
+            color = "\033[94m";  // blue 
+        } else if(strcmp(argv[1], "-rainbow") == 0){
+                rainbow = 1;  // enable rainbow effect
+        }
+    }
+    printf("Color code set to: %s\n", color);
+
+    clear_screen();  // clear screen b4 starting effect
+    matrix_effect(rows, cols, max_iter, color, rainbow);  // call the matrix effect
+
+    return 0;
+}
+