Initial commit.

graphics.c

@@ -0,0 +1,83 @@
+
+#include <stdio.h>
+
+#define uint unsigned int
+#define ON 'x'
+#define OFF '-'
+
+typedef struct Canvas {
+	int x;
+	int y;
+	char* data;
+} Canvas;
+
+/*
+ * Draws an x*y rectangle with the characters in canvas* c
+ */
+void render(Canvas* c){
+	putchar('\n');
+
+	for(int i=0; i < c->y; i++){
+		for(int j=0; j < c->x; j++){
+			putchar(c->data[i*(c->x)+j]);	
+		}
+		putchar('\n');
+	}
+}
+
+/*
+ * Sets pixel at x,y to ON
+ */
+void dot(Canvas* c, uint x, uint y){	
+	c->data[ y*(c->x) + x] = ON;
+}
+
+
+/*
+ * Draws a line from (start_x, start_y) to (end_x, end_y)
+ */
+void line(Canvas* c, uint start_x, uint start_y, uint end_x, uint end_y){
+#ifndef abs
+#define abs(x) ((x<0)?(-x):(x))
+
+	
+	int dx = abs(end_x - start_x);
+	int dy = abs(end_y - start_y);
+
+	int direction_x = start_x < end_x ? 1 : -1;
+	int direction_y = start_y < end_y ? 1 : -1;
+
+	printf("dx:%i dy:%i direction:%i,%i", dx, dy, direction_x, direction_y);
+
+	if(dx>dy){
+		for(int i=0; i<dx; i++){
+			dot(c, start_x+i*direction_x, start_y+(dy/(i+1))*direction_y);
+		}
+	}else{
+		for(int i=0; i<dy; i++){
+			dot(c, start_x+(dx/(i+1))*direction_x, start_y+i*direction_y);
+		}
+	}
+
+#undef abs
+#endif
+}
+
+
+int main(){
+	char data[] =
+		"---"
+		"---"
+		"---";
+
+	Canvas a = {3, 3, data};
+
+	//line(&a, 0, 0, 3, 3);
+
+	dot(&a, 0, 0);
+	dot(&a, 2, 2);
+
+	render(&a);
+
+	return 0;
+}