Merge pull request #17 from ihateamongus/codex/add-staggering-color-effect-demo-in-tools

Add color staggering X demo

2 files changed, 106 insertions, 5 deletions

diff --git a/tools/Makefile b/tools/Makefile
index ae33902..e42f8bf 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -1,16 +1,20 @@
+.RECIPEPREFIX = >
 CC = cc
 CFLAGS = -std=c99 -Wall -Wextra -pedantic -Os
 LDFLAGS =
 PREFIX ?= /usr/local
 
-all: exofetch
+all: exofetch colorstagger
 
 exofetch: exofetch.c
-	$(CC) $(CFLAGS) -o $@ $< $(LDFLAGS)
+>$(CC) $(CFLAGS) -o $@ $< $(LDFLAGS)
+
+colorstagger: colorstagger.c
+>$(CC) $(CFLAGS) -o $@ $< $(LDFLAGS) -lX11
 
 clean:
-	rm -f exofetch
+>rm -f exofetch colorstagger
 
 install: exofetch
-	mkdir -p $(DESTDIR)$(PREFIX)/bin
-	cp -f exofetch $(DESTDIR)$(PREFIX)/bin
+>mkdir -p $(DESTDIR)$(PREFIX)/bin
+>cp -f exofetch $(DESTDIR)$(PREFIX)/bin
diff --git a/tools/colorstagger.c b/tools/colorstagger.c
new file mode 100644
index 0000000..3e68faf
--- /dev/null
+++ b/tools/colorstagger.c
@@ -0,0 +1,97 @@
+#define _XOPEN_SOURCE 500
+#include <X11/Xlib.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+typedef struct { unsigned char r, g, b; } Color;
+
+static Color
+parse(const char *hex)
+{
+    Color c = {0};
+    if (hex[0] == '#')
+        hex++;
+    if (strlen(hex) >= 6) {
+        char buf[3] = {0};
+        buf[0] = hex[0]; buf[1] = hex[1]; c.r = strtol(buf, NULL, 16);
+        buf[0] = hex[2]; buf[1] = hex[3]; c.g = strtol(buf, NULL, 16);
+        buf[0] = hex[4]; buf[1] = hex[5]; c.b = strtol(buf, NULL, 16);
+    }
+    return c;
+}
+
+static unsigned long
+pack(Color c)
+{
+    return ((unsigned long)c.r << 16) |
+           ((unsigned long)c.g << 8) |
+           ((unsigned long)c.b);
+}
+
+static Color
+mix(Color a, Color b, double t)
+{
+    Color c;
+    c.r = a.r + (b.r - a.r) * t;
+    c.g = a.g + (b.g - a.g) * t;
+    c.b = a.b + (b.b - a.b) * t;
+    return c;
+}
+
+int
+main(void)
+{
+    char *colors[] = {"#ff5555", "#f1fa8c", "#50fa7b", "#8be9fd", "#bd93f9"};
+    const int ncolors = sizeof(colors) / sizeof(colors[0]);
+
+    Display *d = XOpenDisplay(NULL);
+    if (!d) {
+        fprintf(stderr, "cannot open display\n");
+        return 1;
+    }
+    int s = DefaultScreen(d);
+    int width = 600, height = 100;
+    Window w = XCreateSimpleWindow(d, RootWindow(d, s), 10, 10, width, height,
+                                   1, BlackPixel(d, s), WhitePixel(d, s));
+    XSelectInput(d, w, KeyPressMask);
+    XMapWindow(d, w);
+    GC gc = XCreateGC(d, w, 0, NULL);
+
+    int grad = 60, solid = 60;
+    int running = 1;
+    while (running) {
+        while (XPending(d)) {
+            XEvent e;
+            XNextEvent(d, &e);
+            if (e.type == KeyPress)
+                running = 0;
+        }
+
+        int x = 0;
+        for (int i = 0; i < ncolors; i++) {
+            Color a = parse(colors[i]);
+            Color b = parse(colors[(i + 1) % ncolors]);
+            for (int k = 0; k < grad; k++) {
+                double t = k / (double)(grad - 1);
+                Color c = mix(a, b, t);
+                XSetForeground(d, gc, pack(c));
+                XDrawLine(d, w, gc, x + k, 0, x + k, height);
+            }
+            x += grad;
+            XSetForeground(d, gc, pack(b));
+            XFillRectangle(d, w, gc, x, 0, solid, height);
+            x += solid;
+        }
+        XFlush(d);
+        usleep(500000);
+        char *tmp = colors[0];
+        memmove(colors, colors + 1, (ncolors - 1) * sizeof(char *));
+        colors[ncolors - 1] = tmp;
+        XClearWindow(d, w);
+    }
+
+    XCloseDisplay(d);
+    return 0;
+}