LOLWUT: refactoring + skeleton of LOLWUT 6.

1 files changed, 2 insertions, 108 deletions

diff --git a/src/lolwut5.c b/src/lolwut5.c
index 52a98c0d7..4e9828145 100644
--- a/src/lolwut5.c
+++ b/src/lolwut5.c
@@ -34,17 +34,9 @@
  */
 
 #include "server.h"
+#include "lolwut.h"
 #include <math.h>
 
-/* This structure represents our canvas. Drawing functions will take a pointer
- * to a canvas to write to it. Later the canvas can be rendered to a string
- * suitable to be printed on the screen, using unicode Braille characters. */
-typedef struct lwCanvas {
-    int width;
-    int height;
-    char *pixels;
-} lwCanvas;
-
 /* Translate a group of 8 pixels (2x4 vertical rectangle) to the corresponding
  * braille character. The byte should correspond to the pixels arranged as
  * follows, where 0 is the least significant bit, and 7 the most significant
@@ -69,104 +61,6 @@ void lwTranslatePixelsGroup(int byte, char *output) {
     output[2] = 0x80 | (code & 0x3F);         /* 10-xxxxxx */
 }
 
-/* Allocate and return a new canvas of the specified size. */
-lwCanvas *lwCreateCanvas(int width, int height) {
-    lwCanvas *canvas = zmalloc(sizeof(*canvas));
-    canvas->width = width;
-    canvas->height = height;
-    canvas->pixels = zmalloc(width*height);
-    memset(canvas->pixels,0,width*height);
-    return canvas;
-}
-
-/* Free the canvas created by lwCreateCanvas(). */
-void lwFreeCanvas(lwCanvas *canvas) {
-    zfree(canvas->pixels);
-    zfree(canvas);
-}
-
-/* Set a pixel to the specified color. Color is 0 or 1, where zero means no
- * dot will be displyed, and 1 means dot will be displayed.
- * Coordinates are arranged so that left-top corner is 0,0. You can write
- * out of the size of the canvas without issues. */
-void lwDrawPixel(lwCanvas *canvas, int x, int y, int color) {
-    if (x < 0 || x >= canvas->width ||
-        y < 0 || y >= canvas->height) return;
-    canvas->pixels[x+y*canvas->width] = color;
-}
-
-/* Return the value of the specified pixel on the canvas. */
-int lwGetPixel(lwCanvas *canvas, int x, int y) {
-    if (x < 0 || x >= canvas->width ||
-        y < 0 || y >= canvas->height) return 0;
-    return canvas->pixels[x+y*canvas->width];
-}
-
-/* Draw a line from x1,y1 to x2,y2 using the Bresenham algorithm. */
-void lwDrawLine(lwCanvas *canvas, int x1, int y1, int x2, int y2, int color) {
-    int dx = abs(x2-x1);
-    int dy = abs(y2-y1);
-    int sx = (x1 < x2) ? 1 : -1;
-    int sy = (y1 < y2) ? 1 : -1;
-    int err = dx-dy, e2;
-
-    while(1) {
-        lwDrawPixel(canvas,x1,y1,color);
-        if (x1 == x2 && y1 == y2) break;
-        e2 = err*2;
-        if (e2 > -dy) {
-            err -= dy;
-            x1 += sx;
-        }
-        if (e2 < dx) {
-            err += dx;
-            y1 += sy;
-        }
-    }
-}
-
-/* Draw a square centered at the specified x,y coordinates, with the specified
- * rotation angle and size. In order to write a rotated square, we use the
- * trivial fact that the parametric equation:
- *
- *  x = sin(k)
- *  y = cos(k)
- *
- * Describes a circle for values going from 0 to 2*PI. So basically if we start
- * at 45 degrees, that is k = PI/4, with the first point, and then we find
- * the other three points incrementing K by PI/2 (90 degrees), we'll have the
- * points of the square. In order to rotate the square, we just start with
- * k = PI/4 + rotation_angle, and we are done.
- *
- * Of course the vanilla equations above will describe the square inside a
- * circle of radius 1, so in order to draw larger squares we'll have to
- * multiply the obtained coordinates, and then translate them. However this
- * is much simpler than implementing the abstract concept of 2D shape and then
- * performing the rotation/translation transformation, so for LOLWUT it's
- * a good approach. */
-void lwDrawSquare(lwCanvas *canvas, int x, int y, float size, float angle) {
-    int px[4], py[4];
-
-    /* Adjust the desired size according to the fact that the square inscribed
-     * into a circle of radius 1 has the side of length SQRT(2). This way
-     * size becomes a simple multiplication factor we can use with our
-     * coordinates to magnify them. */
-    size /= 1.4142135623;
-    size = round(size);
-
-    /* Compute the four points. */
-    float k = M_PI/4 + angle;
-    for (int j = 0; j < 4; j++) {
-        px[j] = round(sin(k) * size + x);
-        py[j] = round(cos(k) * size + y);
-        k += M_PI/2;
-    }
-
-    /* Draw the square. */
-    for (int j = 0; j < 4; j++)
-        lwDrawLine(canvas,px[j],py[j],px[(j+1)%4],py[(j+1)%4],1);
-}
-
 /* Schotter, the output of LOLWUT of Redis 5, is a computer graphic art piece
  * generated by Georg Nees in the 60s. It explores the relationship between
  * caos and order.
@@ -200,7 +94,7 @@ lwCanvas *lwDrawSchotter(int console_cols, int squares_per_row, int squares_per_
                 sx += r2*square_side/3;
                 sy += r3*square_side/3;
             }
-            lwDrawSquare(canvas,sx,sy,square_side,angle);
+            lwDrawSquare(canvas,sx,sy,square_side,angle,1);
         }
     }