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Author SHA1 Message Date
a450f351c5 add vibecoded artnet lib 2025-12-17 02:24:38 +01:00
97e9a03610 restructure 2025-12-17 02:00:39 +01:00
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6c4da20268 view from above, not center 2025-12-13 01:38:43 +00:00
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44efb66411 convert to c program 2025-12-13 01:33:41 +00:00
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db764bbac0 change x scale 2025-12-13 00:42:20 +00:00
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4d2ef1a667 gpt answer with sloped lines 2025-12-13 00:33:58 +00:00
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25c4054dbc wire 2025-12-12 23:15:50 +00:00
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9f3754a71a filled rectangles 2025-12-12 22:56:30 +00:00
7 changed files with 645 additions and 0 deletions

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/* --------------------------------------------------------------------
* artnet_receiver.c tiny ArtNet DMX receiver
* -------------------------------------------------------------------- */
#define _POSIX_C_SOURCE 200112L
#include "artnet_receiver.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <pthread.h>
#include <errno.h>
#define ARTNET_PORT 6454
#define ARTNET_HEADER_SIZE 18 /* "Art-Net\0" + OpCode + … */
#define OP_DMX 0x5000 /* lowbyte first (littleendian) */
/* --------------------------------------------------------------- */
static int artnet_sock = -1;
static pthread_t receiver_thread;
static volatile bool run_thread = false;
/* -----------------------------------------------------------------
* Helper: map a DMX byte (0255) to a signed or unsigned integer
* ----------------------------------------------------------------- */
static inline int map_range_uint8(uint8_t v, int dst_min, int dst_max)
{
return dst_min + (int)((v * (dst_max - dst_min)) / 255.0);
}
/* -----------------------------------------------------------------
* The thread that receives ArtNet packets
* ----------------------------------------------------------------- */
static void *receiver_func(void *arg)
{
(void)arg; /* unused */
struct sockaddr_in from;
socklen_t fromlen = sizeof(from);
uint8_t buf[1500]; /* big enough for a full packet */
while (run_thread) {
ssize_t n = recvfrom(artnet_sock, buf, sizeof(buf), 0,
(struct sockaddr *)&from, &fromlen);
if (n < 0) {
if (errno == EINTR) continue;
perror("recvfrom");
continue;
}
/* ------------------ quick sanity checks ------------------- */
if (n < ARTNET_HEADER_SIZE) continue; /* too short */
if (memcmp(buf, "Art-Net\0", 8) != 0) continue; /* not ArtNet */
uint16_t opcode = buf[8] | (buf[9] << 8); /* littleendian */
if (opcode != OP_DMX) continue; /* not ArtDMX */
/* --------------------- DMX payload ----------------------- */
uint16_t universe = buf[14] | (buf[15] << 8); /* not used */
uint16_t length = buf[16] << 8 | buf[17]; /* bigendian */
if (length + ARTNET_HEADER_SIZE != (size_t)n) continue; /* malformed */
uint8_t *dmx = buf + ARTNET_HEADER_SIZE; /* first DMX slot */
/* --------------------- update shared variables ------------ */
/* 0 … 11 → rotation angles (0180°) */
for (int i = 0; i < 12 && i < length; ++i) {
rotAnglesDeg[i] = map_range_uint8(dmx[i], 0, 180);
}
///* channel 12 → line thickness (110) */
//if (length > 12) {
// LINE_THICKNESS = map_range_uint8(dmx[12], 1, 10);
//}
///* channel 13 → top margin (0200px) */
//if (length > 13) {
// MARGIN_TOP = map_range_uint8(dmx[13], 0, 200);
//}
///* channel 14 → bottom margin (0200px) */
//if (length > 14) {
// MARGIN_BOTTOM = map_range_uint8(dmx[14], 0, 200);
//}
/* (Add more channels here if you need them) */
}
return NULL;
}
/* -----------------------------------------------------------------
* Public API
* ----------------------------------------------------------------- */
bool artnet_init(void)
{
struct sockaddr_in sa;
artnet_sock = socket(AF_INET, SOCK_DGRAM, 0);
if (artnet_sock < 0) {
perror("socket");
return false;
}
memset(&sa, 0, sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = htonl(INADDR_ANY);
sa.sin_port = htons(ARTNET_PORT);
if (bind(artnet_sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
perror("bind");
close(artnet_sock);
artnet_sock = -1;
return false;
}
run_thread = true;
if (pthread_create(&receiver_thread, NULL, receiver_func, NULL) != 0) {
perror("pthread_create");
close(artnet_sock);
artnet_sock = -1;
run_thread = false;
return false;
}
return true;
}
void artnet_stop(void)
{
if (!run_thread) return;
run_thread = false;
/* Wake the thread if it is blocked in recvfrom */
shutdown(artnet_sock, SHUT_RDWR);
pthread_join(receiver_thread, NULL);
close(artnet_sock);
artnet_sock = -1;
}

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/* --------------------------------------------------------------------
* artnet_receiver.c tiny ArtNet DMX receiver
*
* This file contains only the pieces you need to:
* * open a UDP socket on port 6454,
* * receive ArtDMX packets,
* * extract the DMX data (up to 512 bytes),
* * copy the first N bytes into the variables of the main program.
*
* The code is deliberately simple it ignores ArtPoll, ArtSync,
* multiple universes, etc. If you need those features you can replace
* the receive loop with libartnet or another full implementation.
* -------------------------------------------------------------------- */
#ifndef ARTNET_RECEIVER_H
#define ARTNET_RECEIVER_H
#include <stddef.h>
#include <stdint.h>
#include <stdbool.h>
#include <pthread.h>
/* ---------------------------------------------------------------
* Public API call from the main program
*
* artnet_init() : creates the receiving thread.
* artnet_stop() : asks the thread to terminate and joins it.
* --------------------------------------------------------------- */
bool artnet_init(void); /* returns true on success */
void artnet_stop(void);
/* ---------------------------------------------------------------
* The variables that the ArtNet thread will write to.
* They are declared `extern` here and defined in the main file.
* --------------------------------------------------------------- */
extern int16_t rotAnglesDeg[12]; /* 0 … 180° (mapped from 0255) */
extern int LINE_THICKNESS; /* 1 … 10 (clamped) */
extern int MARGIN_TOP; /* 0 … 200px (scaled) */
extern int MARGIN_BOTTOM; /* 0 … 200px (scaled) */
#endif /* ARTNET_RECEIVER_H */

243
draw_parra/dmx2img.c Normal file
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/*=====================================================================
draw_12_tilted_rects.c
---------------------------------------------------------------
Creates an 800×600 ARGB framebuffer, draws 12 white rectangles
whose top and bottom edges are slanted (as in the Python example
you supplied) and streams the buffer to a TCP server on
localhost:12345.
Compile (Linux / macOS):
gcc -Wall -O2 draw_12_tilted_rects.c -lm -o draw_12_tilted_rects
Run:
./draw_12_tilted_rects
-------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <math.h>
#include <errno.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include "artnet_receiver.h"
#define FB_W 800 /* framebuffer width */
#define FB_H 600 /* framebuffer height */
#define BPP 4 /* bytes per pixel (A,R,G,B) */
#define FRAMEBUF_SIZE (FB_W * FB_H * BPP)
#define MARGIN_TOP 100
#define MARGIN_BOTTOM 150
#define SPACING 10 /* space between rectangles */
#define LINE_THICKNESS 4 /* thickness of outline (pixels) */
#define NUM_RECTS 12
///*---------------------------------------------------------------*/
///* 1. Perrectangle tilt angles (in degrees). Edit as you wish. */
int16_t rotAnglesDeg[NUM_RECTS] = {
0, 5, 10, 15, 20, 25,
30, 35, 40, 45, 50, 55
};
/*---------------------------------------------------------------*/
/* 2. ARGB colour helpers */
static const uint32_t COL_BLACK = 0xFF000000; /* opaque black */
static const uint32_t COL_WHITE = 0xFFFFFFFF; /* opaque white */
/*---------------------------------------------------------------*/
/* 3. Simple pixel write (boundschecked) */
static inline void set_pixel(uint8_t *fb, int x, int y, uint32_t col)
{
if (x < 0 || x >= FB_W || y < 0 || y >= FB_H)
return; /* ignore outofbounds writes */
uint32_t *dst = (uint32_t *)(fb + (y * FB_W + x) * BPP);
*dst = col;
}
/*---------------------------------------------------------------*/
/* 4. Thick line Bresenham + square brush */
static void draw_thick_line(uint8_t *fb,
int x0, int y0,
int x1, int y1,
uint32_t col,
int thickness)
{
int dx = abs(x1 - x0);
int dy = -abs(y1 - y0);
int sx = (x0 < x1) ? 1 : -1;
int sy = (y0 < y1) ? 1 : -1;
int err = dx + dy; /* error term */
while (1) {
/* paint a square centred on the current pixel */
for (int ty = -thickness/2; ty <= thickness/2; ++ty) {
for (int tx = -thickness/2; tx <= thickness/2; ++tx) {
set_pixel(fb, x0 + tx, y0 + ty, col);
}
}
if (x0 == x1 && y0 == y1) break;
int e2 = 2 * err;
if (e2 >= dy) { err += dy; x0 += sx; }
if (e2 <= dx) { err += dx; y0 += sy; }
}
}
/*---------------------------------------------------------------*/
/* 5. Build the whole framebuffer */
static void build_framebuffer(uint8_t *fb)
{
/* 5.1 background = opaque black */
for (size_t i = 0; i < FRAMEBUF_SIZE; ++i) fb[i] = 0;
uint32_t *pix = (uint32_t *)fb;
for (size_t i = 0; i < FB_W * FB_H; ++i) pix[i] = COL_BLACK;
/* 5.2 geometry that does NOT depend on the angle */
const int usable_h = FB_H - MARGIN_TOP - MARGIN_BOTTOM; /* 400 */
const int rect_h = usable_h; /* 400 */
const int rect_w = rect_h / 8; /* ≈33 */
const int half_w = rect_w / 2;
const int total_rect_w = NUM_RECTS * rect_w + (NUM_RECTS - 1) * SPACING;
const int x0_start = (FB_W - total_rect_w) / 2; /* centre strip */
const int y_top = MARGIN_TOP;
const int y_bottom = FB_H - MARGIN_BOTTOM - 1; /* inclusive */
/* 5.3 draw each rectangle */
for (int i = 0; i < NUM_RECTS; ++i) {
/* ---- centre X (kept fixed while tilting) ---- */
int orig_x0 = x0_start + i * (rect_w + SPACING);
int cx = orig_x0 + half_w; /* centre X coordinate */
/* ---- angle in radians, sin and cos ---- */
double angle_rad = rotAnglesDeg[i] * M_PI / 180.0;
double sin_a = sin(angle_rad);
double cos_a = cos(angle_rad);
/* ---- vertical offset applied to the endpoints of the top/bottom lines ---- */
double offset = sin_a * half_w; /* sin(angle) * (RECT_W/2) */
/* ---- X offsets for the slanted top/bottom edges ---- */
double x_offset = cos_a * half_w; /* cos(angle) * (RECT_W/2) */
/* ---- compute the four endpoints (rounded to nearest integer) ---- */
int x0_top = (int)round(cx - x_offset);
int y0_top = (int)round(y_top + offset);
int x1_top = (int)round(cx + x_offset);
int y1_top = (int)round(y_top - offset);
int x0_bot = (int)round(cx - x_offset);
int y0_bot = (int)round(y_bottom + offset);
int x1_bot = (int)round(cx + x_offset);
int y1_bot = (int)round(y_bottom - offset);
/* ---- draw the four sides (thick) ---- */
draw_thick_line(fb, x0_top, y0_top, x1_top, y1_top,
COL_WHITE, LINE_THICKNESS); /* top */
draw_thick_line(fb, x0_bot, y0_bot, x1_bot, y1_bot,
COL_WHITE, LINE_THICKNESS); /* bottom*/
/* vertical sides use the X coordinates of the *top* points;
the Ycoordinates are taken from the corresponding top/bottom
endpoint, therefore they are automatically different when the
angle ≠ 0 or 180. */
draw_thick_line(fb, x0_top, y0_top, x0_bot, y0_bot,
COL_WHITE, LINE_THICKNESS); /* left */
draw_thick_line(fb, x1_top, y1_top, x1_bot, y1_bot,
COL_WHITE, LINE_THICKNESS); /* right */
}
}
/*---------------------------------------------------------------*/
/* 6. Send the framebuffer over TCP (lengthprefixed) */
static int send_framebuffer(const uint8_t *fb, size_t len,
const char *host, uint16_t port)
{
struct sockaddr_in srv;
int sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket");
return -1;
}
memset(&srv, 0, sizeof(srv));
srv.sin_family = AF_INET;
srv.sin_port = htons(port);
if (inet_pton(AF_INET, host, &srv.sin_addr) <= 0) {
perror("inet_pton");
close(sock);
return -1;
}
if (connect(sock, (struct sockaddr *)&srv, sizeof(srv)) < 0) {
perror("connect");
close(sock);
return -1;
}
/* ---- optional 4byte length prefix (bigendian) ---- */
uint32_t be_len = htonl((uint32_t)len);
if (write(sock, &be_len, sizeof(be_len)) != sizeof(be_len)) {
perror("write length prefix");
close(sock);
return -1;
}
/* ---- send the raw buffer ---- */
size_t sent = 0;
while (sent < len) {
ssize_t n = write(sock, fb + sent, len - sent);
if (n <= 0) {
perror("write framebuffer");
close(sock);
return -1;
}
sent += n;
}
close(sock);
return 0;
}
/*---------------------------------------------------------------*/
int main(void)
{
/* ---------------------------------------------------------------
* 1⃣ Start ArtNet receiver it will fill the globals
* --------------------------------------------------------------- */
if (!artnet_init()) {
fprintf(stderr, "Failed to start ArtNet receiver\n");
return EXIT_FAILURE;
}
uint8_t *framebuf = malloc(FRAMEBUF_SIZE);
if (!framebuf) {
fprintf(stderr, "Failed to allocate framebuffer (%zu bytes)\n",
(size_t)FRAMEBUF_SIZE);
return EXIT_FAILURE;
}
while(1){
//for(uint8_t i=0; i<sizeof(rotAnglesDeg)/sizeof(rotAnglesDeg[0]); i++)
// rotAnglesDeg[i]=(rotAnglesDeg[i]+3)%180;
build_framebuffer(framebuf);
if (send_framebuffer(framebuf, FRAMEBUF_SIZE, "127.0.0.1", 12345) != 0) {
fprintf(stderr, "Failed to send framebuffer\n");
free(framebuf);
return EXIT_FAILURE;
}
usleep(100000);
}
printf("Framebuffer (%zu bytes) sent successfully.\n", (size_t)FRAMEBUF_SIZE);
free(framebuf);
return EXIT_SUCCESS;
}

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#!/usr/bin/env python3
"""
draw_12_slanted_top_bottom.py
* 800×600 ARGB framebuffer (A,R,G,B each 1byte)
* 12 rectangles, aspect1:12, 5px gap, 100px empty margin at top & bottom
* each rectangle has an individual tilt angle (degrees) stored in
ROT_ANGLES_DEG[12]
* the top and bottom edges are *slanted* while the left and righthand
edges remain perfectly vertical
* outline colour = opaque white, thickness = LINE_THICKNESS (default=3px)
* the raw buffer (with a 4byte length prefix) is streamed to a TCP server
listening on localhost:12345
"""
import math
import socket
import sys
# ----------------------------------------------------------------------
# 1⃣ Framebuffer configuration
# ----------------------------------------------------------------------
FB_WIDTH = 800 # horizontal pixels
FB_HEIGHT = 600 # vertical pixels
BPP = 4 # bytes per pixel (A,R,G,B)
# ----------------------------------------------------------------------
# 2⃣ Margins & rectangle geometry (before slant)
# ----------------------------------------------------------------------
MARGIN_TOP = 100 # empty band at the very top
MARGIN_BOTTOM = 150 # empty band at the very bottom
RECT_HEIGHT = FB_HEIGHT - MARGIN_TOP - MARGIN_BOTTOM # usable height = 400px
RECT_WIDTH = RECT_HEIGHT // 12 # ≈33px (aspect1:12)
SPACING = 10 # gap between rectangles
TOTAL_RECT_W = 12 * RECT_WIDTH + 11 * SPACING
X0_START = (FB_WIDTH - TOTAL_RECT_W) // 2 # centre the whole strip
# ----------------------------------------------------------------------
# 3⃣ Outline thickness (you may change it)
# ----------------------------------------------------------------------
LINE_THICKNESS = 5 # ≥1 pixel
# ----------------------------------------------------------------------
# 4⃣ Perrectangle tilt angles (degrees)
# ----------------------------------------------------------------------
# You can generate these programmatically, read them from a file, etc.
ROT_ANGLES_DEG = [
0, 5, 10, 15, 20, 25,
30, 35, 40, 45, 50, 85
]
assert len(ROT_ANGLES_DEG) == 12, "Exactly 12 angles are required."
# ----------------------------------------------------------------------
# Helper write a single pixel (boundschecked)
# ----------------------------------------------------------------------
def set_pixel(buf: bytearray, x: int, y: int, color: tuple) -> None:
"""Write an ARGB pixel at (x, y). `color` = (A,R,G,B)."""
if 0 <= x < FB_WIDTH and 0 <= y < FB_HEIGHT:
off = (y * FB_WIDTH + x) * BPP
buf[off:off + 4] = bytes(color) # A,R,G,B order
# ----------------------------------------------------------------------
# Helper draw a thick line (Bresenham + square brush)
# ----------------------------------------------------------------------
def draw_thick_line(buf: bytearray,
x0: int, y0: int,
x1: int, y1: int,
color: tuple,
thickness: int) -> None:
"""Draw a line from (x0,y0) to (x1,y1) using a square brush of `thickness`."""
dx = abs(x1 - x0)
dy = -abs(y1 - y0)
sx = 1 if x0 < x1 else -1
sy = 1 if y0 < y1 else -1
err = dx + dy # error term
while True:
# paint a filled square centred on the current pixel
for ty in range(-thickness // 2, thickness // 2 + 1):
for tx in range(-thickness // 2, thickness // 2 + 1):
set_pixel(buf, x0 + tx, y0 + ty, color)
if x0 == x1 and y0 == y1:
break
e2 = 2 * err
if e2 >= dy:
err += dy
x0 += sx
if e2 <= dx:
err += dx
y0 += sy
# ----------------------------------------------------------------------
# 5⃣ Build the framebuffer (background + white slantedtop/bottom rectangles)
# ----------------------------------------------------------------------
def build_framebuffer() -> bytearray:
"""Create the ARGB buffer and draw the 12 rectangles with slanted top/bottom."""
# ----- background: opaque black -----
fb = bytearray(FB_WIDTH * FB_HEIGHT * BPP)
bg = (255, 0, 0, 0) # A,R,G,B = opaque black
fb[:] = bg * (FB_WIDTH * FB_HEIGHT)
WHITE = (255, 255, 255, 255) # colour of the outlines
half_w = RECT_WIDTH // 2 # half the (unslanted) width
y_top = MARGIN_TOP
y_bottom = FB_HEIGHT - MARGIN_BOTTOM - 1 # inclusive bottom row
for idx in range(12):
# --------------------------------------------------------------
# 1⃣ Unslanted left edge of the rectangle (including spacing)
# --------------------------------------------------------------
orig_x0 = X0_START + idx * (RECT_WIDTH + SPACING)
# --------------------------------------------------------------
# 2⃣ Centre X coordinate (kept fixed while slanting)
# --------------------------------------------------------------
cx = orig_x0 + half_w
# --------------------------------------------------------------
# 3⃣ Angle for this rectangle
# --------------------------------------------------------------
angle_rad = math.radians(ROT_ANGLES_DEG[idx])
sin_a = math.sin(angle_rad)
# --------------------------------------------------------------
# 4⃣ Vertical offset applied to the *ends* of the top/bottom lines
# (the spec says: sin(angle) * RECT_WITH / 2)
# --------------------------------------------------------------
offset = sin_a * half_w # because RECT_WITH/2 == half_w
# --------------------------------------------------------------
# 5⃣ Coordinates of the four line endpoints
# --------------------------------------------------------------
# top edge
x0_top = cx - int(math.cos(angle_rad) * half_w)
y0_top = int(round(y_top + offset))
x1_top = cx + int(math.cos(angle_rad) * half_w)
y1_top = int(round(y_top - offset))
# bottom edge
x0_bot = cx - int(math.cos(angle_rad) * half_w)
y0_bot = int(round(y_bottom - offset))
x1_bot = cx + int(math.cos(angle_rad) * half_w)
y1_bot = int(round(y_bottom + offset))
# --------------------------------------------------------------
# 6⃣ Draw the four sides
# --------------------------------------------------------------
# top (slanted)
draw_thick_line(fb, x0_top, y0_top, x1_top, y1_top,
WHITE, LINE_THICKNESS)
# bottom (slanted)
draw_thick_line(fb, x0_bot, y0_bot, x1_bot, y1_bot,
WHITE, LINE_THICKNESS)
# left vertical side from the *topleft* endpoint down to the
# *bottomleft* endpoint
draw_thick_line(fb, x0_top, y0_top, x0_bot, y0_bot,
WHITE, LINE_THICKNESS)
# right vertical side from the *topright* endpoint down to the
# *bottomright* endpoint
draw_thick_line(fb, x1_top, y1_top, x1_bot, y1_bot,
WHITE, LINE_THICKNESS)
return fb
# ----------------------------------------------------------------------
# 6⃣ Send the framebuffer to the TCP server (localhost:12345)
# ----------------------------------------------------------------------
def send_framebuffer(buf: bytearray,
host: str = "127.0.0.1",
port: int = 12345) -> None:
"""Open a TCP socket, connect, and stream the whole framebuffer."""
try:
with socket.create_connection((host, port), timeout=5) as sock:
# optional 4byte length prefix many simple protocols expect it
length_prefix = len(buf).to_bytes(4, byteorder="big")
sock.sendall(length_prefix + buf)
print(f"✔ Sent {len(buf)} bytes to {host}:{port}")
except Exception as exc:
print(f"❌ Could not send framebuffer: {exc}", file=sys.stderr)
# ----------------------------------------------------------------------
# 7⃣ Main entry point
# ----------------------------------------------------------------------
def main() -> None:
fb = build_framebuffer()
send_framebuffer(fb)
if __name__ == "__main__":
main()

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draw_parra/makefile Normal file
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CC := gcc
CFLAGS := -Wall -Wextra -pthread
LDLIBS := -lc -lm
TARGET := dmx2img
SRC := dmx2img.c artnet_receiver.c
# -------------------------------------------------
# Default target just type `make` to build
all: $(TARGET)
# How to build the executable
$(TARGET): $(SRC)
$(CC) $(CFLAGS) $^ $(LDLIBS) -o $@
# Convenience: `make clean` to remove the binary
clean:
rm -f $(TARGET)
.PHONY: all clean