Reunify gfx and bin

1 files changed, 151 insertions, 0 deletions

diff --git a/bin/brot.c b/bin/brot.c
new file mode 100644
index 00000000..e7ac442d
--- /dev/null
+++ b/bin/brot.c
@@ -0,0 +1,151 @@
+/* Copyright (C) 2018  C. McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <complex.h>
+#include <err.h>
+#include <math.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "gfx.h"
+
+static uint32_t rgb(uint8_t r, uint8_t g, uint8_t b) {
+	return (uint32_t)r << 16 | (uint32_t)g << 8 | (uint32_t)b;
+}
+static uint32_t gray(uint8_t n) {
+	return rgb(n, n, n);
+}
+
+static double absSq(double complex z) {
+	return creal(z) * creal(z) + cimag(z) * cimag(z);
+}
+
+static uint32_t depth = 50;
+
+static uint32_t mandelbrot(double complex c) {
+	double complex z = 0;
+	for (uint32_t i = 0; i < depth; ++i) {
+		if (absSq(z) > 4.0) return i;
+		z = z * z + c;
+	}
+	return 0;
+}
+
+static double complex translate = -0.75;
+static double complex transform = 2.5;
+
+static uint32_t samples = 1;
+
+static void sample(uint32_t *buf, size_t width, size_t height) {
+	double yRatio = (height > width) ? (double)height / (double)width : 1.0;
+	double xRatio = (width > height) ? (double)width / (double)height : 1.0;
+
+	memset(buf, 0, 4 * width * height);
+	size_t superWidth = width * samples;
+	size_t superHeight = height * samples;
+	for (size_t y = 0; y < superHeight; ++y) {
+		for (size_t x = 0; x < superWidth; ++x) {
+			double zx = (((double)x + 0.5) / (double)superWidth - 0.5) * xRatio;
+			double zy = (((double)y + 0.5) / (double)superHeight - 0.5) * yRatio;
+			uint32_t n = mandelbrot((zx + zy * I) * transform + translate);
+			buf[(y / samples) * width + (x / samples)] += n;
+		}
+	}
+}
+
+static void color(uint32_t *buf, size_t width, size_t height) {
+	for (size_t i = 0; i < width * height; ++i) {
+		buf[i] = gray(255 * buf[i] / samples / samples / depth);
+	}
+}
+
+static double frameTime;
+void draw(uint32_t *buf, size_t width, size_t height) {
+	clock_t t0 = clock();
+	sample(buf, width, height);
+	color(buf, width, height);
+	frameTime = (double)(clock() - t0) / (double)CLOCKS_PER_SEC;
+}
+
+static double translateStep = 1.0 / 128.0;
+static double rotateStep = 1.0 / 128.0;
+static double scaleStep = 1.0 / 32.0;
+
+bool input(char in) {
+	const double PI = acos(-1.0);
+	switch (in) {
+		break; case 'q': return false;
+		break; case '.': depth++;
+		break; case ',': if (depth > 1) depth--;
+		break; case 'l': translate += translateStep * transform;
+		break; case 'h': translate -= translateStep * transform;
+		break; case 'j': translate += translateStep * I * transform;
+		break; case 'k': translate -= translateStep * I * transform;
+		break; case 'u': transform *= cexp(rotateStep * PI * I);
+		break; case 'i': transform /= cexp(rotateStep * PI * I);
+		break; case '+': transform *= 1.0 - scaleStep;
+		break; case '-': transform /= 1.0 - scaleStep;
+		break; case '0': translate = -0.75; transform = 2.5;
+		break; case ']': samples++;
+		break; case '[': if (samples > 1) samples--;
+	}
+	return true;
+}
+
+const char *status(void) {
+	static char buf[256];
+	snprintf(
+		buf, sizeof(buf),
+		"brot -s %u -i %u -t %g%+gi -f %g%+gi # %.6f",
+		samples, depth,
+		creal(translate), cimag(translate),
+		creal(transform), cimag(transform),
+		frameTime
+	);
+	return buf;
+}
+
+static double complex parseComplex(const char *str) {
+	double real = 0.0, imag = 0.0;
+	real = strtod(str, (char **)&str);
+	if (str[0] == 'i') {
+		imag = real;
+		real = 0.0;
+	} else if (str[0]) {
+		imag = strtod(str, NULL);
+	}
+	return real + imag * I;
+}
+
+int init(int argc, char *argv[]) {
+	int opt;
+	while (0 < (opt = getopt(argc, argv, "f:i:s:t:"))) {
+		switch (opt) {
+			break; case 'f': transform = parseComplex(optarg);
+			break; case 'i': depth = strtoul(optarg, NULL, 0);
+			break; case 's': samples = strtoul(optarg, NULL, 0);
+			break; case 't': translate = parseComplex(optarg);
+			break; default: return EX_USAGE;
+		}
+	}
+	return EX_OK;
+}