From 58f31d22973f28a27adaa0e9182650cd78111b1e Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Mon, 7 Oct 2019 18:24:34 +0200
Subject: [PATCH] LOLWUT: version 6 initial output. May change a bit.

---
 src/lolwut.c  |  4 ++--
 src/lolwut.h  |  2 +-
 src/lolwut5.c |  2 +-
 src/lolwut6.c | 38 +++++++++++++++++++++++++++++---------
 4 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/src/lolwut.c b/src/lolwut.c
index 7e2ceca78..0e1552ba0 100644
--- a/src/lolwut.c
+++ b/src/lolwut.c
@@ -90,12 +90,12 @@ void lolwutCommand(client *c) {
  * canvas implementation that can be reused.  */
 
 /* Allocate and return a new canvas of the specified size. */
-lwCanvas *lwCreateCanvas(int width, int height) {
+lwCanvas *lwCreateCanvas(int width, int height, int bgcolor) {
     lwCanvas *canvas = zmalloc(sizeof(*canvas));
     canvas->width = width;
     canvas->height = height;
     canvas->pixels = zmalloc(width*height);
-    memset(canvas->pixels,0,width*height);
+    memset(canvas->pixels,bgcolor,width*height);
     return canvas;
 }
 
diff --git a/src/lolwut.h b/src/lolwut.h
index c049ac907..38c0de423 100644
--- a/src/lolwut.h
+++ b/src/lolwut.h
@@ -41,7 +41,7 @@ typedef struct lwCanvas {
 } lwCanvas;
 
 /* Drawing functions implemented inside lolwut.c. */
-lwCanvas *lwCreateCanvas(int width, int height);
+lwCanvas *lwCreateCanvas(int width, int height, int bgcolor);
 void lwFreeCanvas(lwCanvas *canvas);
 void lwDrawPixel(lwCanvas *canvas, int x, int y, int color);
 int lwGetPixel(lwCanvas *canvas, int x, int y);
diff --git a/src/lolwut5.c b/src/lolwut5.c
index 0200fece6..5a9348800 100644
--- a/src/lolwut5.c
+++ b/src/lolwut5.c
@@ -74,7 +74,7 @@ lwCanvas *lwDrawSchotter(int console_cols, int squares_per_row, int squares_per_
     int padding = canvas_width > 4 ? 2 : 0;
     float square_side = (float)(canvas_width-padding*2) / squares_per_row;
     int canvas_height = square_side * squares_per_col + padding*2;
-    lwCanvas *canvas = lwCreateCanvas(canvas_width, canvas_height);
+    lwCanvas *canvas = lwCreateCanvas(canvas_width, canvas_height, 0);
 
     for (int y = 0; y < squares_per_col; y++) {
         for (int x = 0; x < squares_per_row; x++) {
diff --git a/src/lolwut6.c b/src/lolwut6.c
index 8cc8d6e04..44c933629 100644
--- a/src/lolwut6.c
+++ b/src/lolwut6.c
@@ -114,14 +114,34 @@ void generateSkyscraper(lwCanvas *canvas, struct skyscraper *si) {
 
 /* Generate a skyline inspired by the parallax backgrounds of 8 bit games. */
 void generateSkyline(lwCanvas *canvas) {
-    struct skyscraper si = {
-        .xoff = 4,
-        .width = 13,
-        .height = 15,
-        .windows = 1,
-        .color = 1
-    };
-    generateSkyscraper(canvas, &si);
+    struct skyscraper si;
+
+    /* First draw the background skyscraper without windows, using the
+     * two different grays. */
+    si.color = 1;
+    for (int offset = -10; offset < canvas->width;) {
+        offset += rand() % 8;
+        si.xoff = offset;
+        si.width = 10 + rand()%9;
+        si.height = canvas->height/2 + rand()%canvas->height/2;
+        si.windows = 0;
+        si.color = si.color == 1 ? 2 : 1;
+        generateSkyscraper(canvas, &si);
+        offset += si.width/2;
+    }
+
+    /* Now draw the foreground skyscraper with the windows. */
+    si.color = 0;
+    for (int offset = -10; offset < canvas->width;) {
+        offset += rand() % 8;
+        si.xoff = offset;
+        si.width = 5 + rand()%14;
+        if (si.width % 4) si.width += (si.width % 3);
+        si.height = canvas->height/2 + rand()%canvas->height/2;
+        si.windows = 1;
+        generateSkyscraper(canvas, &si);
+        offset += si.width+1;
+    }
 }
 
 /* The LOLWUT 6 command:
@@ -152,7 +172,7 @@ void lolwut6Command(client *c) {
     if (rows > 1000) rows = 1000;
 
     /* Generate the city skyline and reply. */
-    lwCanvas *canvas = lwCreateCanvas(cols,rows);
+    lwCanvas *canvas = lwCreateCanvas(cols,rows,3);
     generateSkyline(canvas);
     sds rendered = renderCanvas(canvas);
     rendered = sdscat(rendered,