Add type for star with Janus cosmological law

CHANGE.md

@@ -0,0 +1,82 @@
+# CHANGELOG
+
+## 2026-02-18
+
+### Added
+
+* Matter distribution selector for Janus initialization:
+  * `Core + halo`
+  * `Random mix`
+  * `Split on X`
+* `Positive Ratio` parameter for random matter assignment.
+* `Core + halo` extra-density slider:
+  * `Extra negative density inside core` in `[0, 1]`
+* Batch simulation mode in executable:
+  * `--batch-steps N`
+  * `--snapshots K`
+  * `--output-dir DIR`
+  * `--config FILE` (load one config line)
+  * `--batch-config FILE` (run one simulation per line)
+* Final snapshot export from multiple camera angles in batch mode.
+* Run helper scripts:
+  * `run_sim.sh`
+  * `run_batch.sh`
+  * `run_batch.sh --batch-config batch_configs/example.batchcfg`
+  * `run_batch.sh` automatically uses root `batch_jobs.cfg` when present
+* In-app batch export UI:
+  * set config output path
+  * append current `SIMCFG` line directly from the menu
+* Root-level batch job template file: `batch_jobs.cfg`
+* Camera preset in config lines:
+  * `camera_view=isometric|top`
+* Root-level interactive startup config file: `simulation.cfg`
+
+### Changed
+
+* Rendering color convention aligned with Janus interpretation:
+  * positive/regular mass rendered in blue
+  * negative mass rendered in red
+* Janus post-process shader simplified to preserve star channel data.
+* Core+halo star assignment logic updated to match model:
+  * positive stars initialized in core sphere (`Type Diameter`)
+  * halo stars initialized as negative (outside core)
+  * `Extra negative density inside core` controls core negative injection in `[0, 1]`
+* Startup logs now print assigned counts (`stars+`, `stars-`, `core`, `halo`).
+* Restart logs now print full one-line configs (`SIMCFG key=value ...`) for copy/paste into batch files.
+
+### Performance
+
+* OpenCL command queue is initialized once and reused.
+* Per-frame scalar parameters are now updated in existing OpenCL buffers.
+* Removed unnecessary per-frame acceleration readback from GPU to CPU.
+* OpenGL VBO is no longer reallocated every frame.
+* Star type data is uploaded once at initialization/restart.
+* Integer star type vertex attribute now uses `glVertexAttribIPointer`.
+
+### Usage
+
+Interactive run:
+
+```bash
+./build/Galaxy_simulation
+bash run_sim.sh
+```
+
+Batch run:
+
+```bash
+./build/Galaxy_simulation --batch-steps 5000 --snapshots 4 --output-dir outputs/run_001
+bash run_batch.sh 5000 4 outputs/run_001
+bash run_batch.sh --batch-config batch_configs/example.batchcfg
+```
+
+### Validation checklist
+
+* Build succeeds: `bash unix_run.sh`.
+* Positive stars appear blue, negative stars appear red.
+* Batch run generates `snapshot_*.png` in output directory.
+* Runtime improves versus previous version for same star count and parameters.
+
+### Known limitation
+
+* Batch mode still requires an OpenGL/X11 context (not true headless yet).

README.md

@@ -27,9 +27,18 @@ This repository contains the source code of an n-body type simulation using GPU
 * **[📋 Summary](#-summary)**
 * **[🎥 Video](#-video)**
 * **[✨ Features](#-features)**
+* **[🐧 Build on Linux](#-build-on-linux)**
 * **[🛠️ Install](#%EF%B8%8F-install)**
-	* [🦴 Skeleton project install](#-skeleton-project-install)
-	* [📦 Additionnal dependencies](#-additionnal-dependencies)
+	* [📦 Dependencies](#-dependencies)
+	* [▶️ Build](#%EF%B8%8F-build)
+	* [🚀 Run](#-run)
+	* [⚙️ Janus + Performance Update](#%EF%B8%8F-janus--performance-update)
+	* [🧪 Batch Experiment Workflow](#-batch-experiment-workflow)
+	* [✅ Validate Optimized Runs](#-validate-optimized-runs)
+	* [☁️ Cloud VM](#%EF%B8%8F-cloud-vm)
+	* [🧩 Troubleshooting](#-troubleshooting)
+* **[📝 Changes](#-changes)**
+* **[🧪 Simulation variants](#-simulation-variants)**
 * **[🗓️ Releases](#%EF%B8%8F-releases)**
 * **[🧪 Tests](#-tests)**
 * **[🙏 Credits](#-credits)**
@@ -68,17 +77,274 @@ Here is a video explaining how the algorithm works : [<u>**Simuler 1 000 000 de
 
 <br/>
 
+# 🐧 Build on Linux
+
+```bash
+bash unix_run.sh
+```
+
+This script:
+
+* initializes/upgrades git submodules (`--init --recursive`)
+* configures CMake with `Unix Makefiles`
+* uses the OpenCL include/library shipped in this repository
+* builds the executable in `./build`
+
+<br/>
+
 # 🛠️ Install
 
-## 🦴 Skeleton project install
+## 📦 Dependencies
+
+On Debian/Ubuntu:
+
+```bash
+sudo apt-get update
+sudo apt-get install -y \
+  build-essential \
+  cmake \
+  libglew-dev \
+  freeglut3-dev \
+  ocl-icd-opencl-dev
+```
+
+On Arch Linux:
+
+```bash
+sudo pacman -S --needed \
+  base-devel \
+  cmake \
+  glew \
+  freeglut \
+  opencl-headers \
+  ocl-icd \
+  clinfo
+```
+
+Install at least one OpenCL implementation:
+
+CPU fallback:
+
+```bash
+sudo pacman -S --needed pocl
+```
+
+NVIDIA GPU:
+
+```bash
+sudo pacman -S --needed opencl-nvidia
+```
+
+## ▶️ Build
+
+If you clone for the first time:
+
+```bash
+git clone --recurse-submodules https://github.com/angeluriot/Galaxy_simulation.git
+cd Galaxy_simulation
+```
+
+Then build:
+
+```bash
+bash unix_run.sh
+```
+
+## 🚀 Run
+
+```bash
+./build/Galaxy_simulation
+```
+
+Shortcut:
+
+```bash
+bash run_sim.sh
+```
+
+Default root config for normal (interactive) simulation:
+
+* `simulation.cfg`
+* when you run `bash run_sim.sh` with no extra arguments, this file is loaded automatically
+* set `camera_view=top` in `simulation.cfg` for top-down startup
+
+Batch run (compute N steps, then export final snapshots from multiple angles):
+
+```bash
+./build/Galaxy_simulation --batch-steps 2000 --snapshots 4 --output-dir outputs
+```
+
+Shortcut:
+
+```bash
+bash run_batch.sh 2000 4 outputs
+```
+
+Batch file (each line = one simulation job):
+
+```bash
+bash run_batch.sh --batch-config batch_configs/example.batchcfg
+```
+
+Default root config:
+
+```bash
+bash run_batch.sh
+```
+
+If `batch_jobs.cfg` exists at repository root, `run_batch.sh` uses it automatically.
+
+## ⚙️ Janus + Performance Update
+
+This branch includes:
+
+* Janus star typing with explicit matter distributions:
+  * `Core + halo` (positive center, negative outer region)
+  * `Random mix` (positive ratio slider)
+  * `Split on X` (two spatial halves)
+* `Core + halo` negative density control:
+  * `Extra negative density inside core` in `[0, 1]`
+  * `0`: core fully positive
+  * `1`: core fully negative
+  * in `Core + halo` mode: halo stars are always negative
+* Janus force multipliers:
+  * `Negative Attraction Constant`
+  * `Repulsion Constant`
+* Color convention:
+  * Positive/regular mass: **blue**
+  * Negative mass: **red**
+* Performance optimizations:
+  * Reuse OpenCL command queue
+  * Reuse scalar OpenCL buffers and update them in-place
+  * Remove unnecessary per-frame acceleration readback
+  * Avoid per-frame OpenGL VBO reallocation
+  * Upload star type data only at initialization/restart
+
+## 🧪 Batch Experiment Workflow
+
+Use batch mode when you want to simulate many frames and only inspect final results:
+
+```bash
+./build/Galaxy_simulation --batch-steps 10000 --snapshots 6 --output-dir outputs/run_001
+```
+
+Run many jobs from one file (line-by-line):
 
-This repository is based on my [**Graphics skeleton project**](https://github.com/angeluriot/Graphics_skeleton), so go see its [**install**](https://github.com/angeluriot/Graphics_skeleton#install) part first.
+```bash
+./build/Galaxy_simulation --batch-config batch_configs/example.batchcfg
+```
+
+Root-level default batch file:
+
+```bash
+./build/Galaxy_simulation --batch-config batch_jobs.cfg
+```
+
+Batch file format:
+
+* each non-comment line is one job
+* each line is `key=value` tokens
+* lines can start with `SIMCFG`
+* recommended keys per line:
+  * simulation: `simulation_type step smoothing_length interaction_rate nb_stars galaxy_diameter galaxy_thickness galaxies_distance stars_speed black_hole_mass negative_attraction_constant repulsion_constant matter_distribution type_diameter positive_ratio core_extra_negative_density camera_view`
+  * batch: `batch_steps snapshots output_dir`
+* `camera_view` values:
+  * `isometric` (default)
+  * `top` (top-down start view)
+
+Recommended workflow:
+
+1. Start interactive mode (`./build/Galaxy_simulation`) and tune settings until the setup is close to your target physics.
+2. Click `Restart` after changing any setting under `Applies after restart`.
+3. In the menu, use `Batch config export`:
+   * set output file path (default: `batch_configs/user.batchcfg`)
+   * click `Append current SIMCFG to file`
+4. Repeat for each setup you want to queue.
+5. Run the whole file with:
+   ```bash
+   bash run_batch.sh --batch-config batch_configs/user.batchcfg
+   ```
+6. Compare the exported snapshots across runs.
+
+Choosing initial parameters:
+
+* `Core + halo`:
+  * `Type Diameter` defines the positive core sphere.
+  * outside that sphere is halo and always negative.
+  * `Extra negative density inside core` injects negative stars into the core (`0` to `1`).
+  * start around `type_diameter = 0.4 * galaxy_diameter` and extra density `0.1`, then sweep.
+* `Random mix`:
+  * use `Positive Ratio` (for example `0.2`, `0.5`, `0.8`) to test segregation behavior.
+* `Split on X`:
+  * good for interface-instability tests.
+* For reduced-particle experiments:
+  * decrease `nb_stars`
+  * compensate dynamics with `Negative Attraction Constant` and `Repulsion Constant`
+  * keep `step` and `smoothing_length` stable while you tune force multipliers.
+
+## ✅ Validate Optimized Runs
+
+Before launching cloud runs, validate local behavior:
+
+1. Build and run:
+   ```bash
+   bash unix_run.sh
+   ./build/Galaxy_simulation
+   ```
+2. Confirm expected visuals:
+   * positive stars are blue
+   * negative stars are red
+3. Confirm initialization counts in terminal logs:
+   * `[Init] stars+=... stars-=... core=... halo=...`
+   * this lets you verify the real positive/negative assignment for each restart
+   * a copy/paste one-line config is printed as:
+     `SIMCFG key=value ...`
+4. Confirm batch export:
+   ```bash
+   ./build/Galaxy_simulation --batch-steps 2000 --snapshots 4 --output-dir outputs/check
+   ```
+5. Compare timing at same parameters before/after optimization.
+
+Notes:
+
+* Batch mode still needs an OpenGL/X11 context on Linux.
+* For server VMs without display, use a virtual display (for example `xvfb`) or add a future true headless mode.
+
+## ☁️ Cloud VM
+
+For remote runs when your local machine is limited:
+
+* setup VM dependencies + build: `bash cloud/setup_ubuntu_vm.sh`
+* run interactive mode over VNC: `VNC_PASSWORD='change_me' bash cloud/start_live_vnc.sh`
+* run headless batch: `bash cloud/run_headless_batch.sh --batch-config batch_configs/example.batchcfg`
+* run queued batch files: `bash cloud/process_batch_queue.sh`
+
+Full guide: [`cloud/README.md`](cloud/README.md)
+
+## 📝 Changes
+
+Detailed change log: see [`CHANGE.md`](CHANGE.md).
+
+## 🧩 Troubleshooting
+
+* `Could not find SFML`: make sure submodules are present (`git submodule update --init --recursive`).
+* `Could NOT find OpenCL`: use `bash unix_run.sh` (it passes the required OpenCL paths).
+* `No platforms found!`: OpenCL loader is present but no OpenCL driver ICD is installed.
+  On Arch Linux:
+  `sudo pacman -S --needed pocl` (CPU fallback) or install the NVIDIA-matching OpenCL package (for example `opencl-nvidia-580xx` for 580xx drivers).
+  Verify with `clinfo`: `Number of platforms` must be at least `1`.
+* `Failed to open X11 display`: run from a desktop session with a valid `DISPLAY` variable.
 
 <br/>
 
-## 📦 Additionnal dependencies
+# 🧪 Simulation variants
 
-Then, you will also need the [**OpenCL**](https://www.khronos.org/opencl/) library.
+* Add different star types at random in proportion.
+* Add different star types from a diameter threshold (current modification).
+* Select matter distribution in-app:
+  * `Core + halo`: positive core, negative halo
+  * `Random mix`: random positive/negative based on ratio
+  * `Split on X`: one half positive, one half negative
 
 <br/>
 

batch_configs/example.batchcfg

@@ -0,0 +1,5 @@
+# Each non-comment line is one simulation job.
+# You can copy/paste SIMCFG lines printed by the app and edit batch_* keys.
+
+SIMCFG simulation_type=Galaxy step=0.001000 smoothing_length=1.000000 interaction_rate=0.050000 nb_stars=30000 galaxy_diameter=100.000000 galaxy_thickness=5.000000 galaxies_distance=75.000000 stars_speed=20.000000 black_hole_mass=1000.000000 negative_attraction_constant=1.000000 repulsion_constant=1.000000 matter_distribution=CoreHalo type_diameter=40.000000 positive_ratio=0.500000 core_extra_negative_density=0.000000 camera_view=isometric batch_steps=3000 snapshots=4 output_dir=outputs/run_core_clean
+SIMCFG simulation_type=Galaxy step=0.001000 smoothing_length=1.000000 interaction_rate=0.050000 nb_stars=30000 galaxy_diameter=100.000000 galaxy_thickness=5.000000 galaxies_distance=75.000000 stars_speed=20.000000 black_hole_mass=1000.000000 negative_attraction_constant=1.000000 repulsion_constant=1.000000 matter_distribution=CoreHalo type_diameter=40.000000 positive_ratio=0.500000 core_extra_negative_density=0.200000 camera_view=top batch_steps=3000 snapshots=4 output_dir=outputs/run_core_mixed

batch_configs/user.batchcfg

@@ -0,0 +1 @@
+SIMCFG simulation_type=Galaxy step=0.001000 smoothing_length=1.000000 interaction_rate=0.050000 nb_stars=20000 galaxy_diameter=100.000000 galaxy_thickness=5.000000 galaxies_distance=75.000000 stars_speed=20.000000 black_hole_mass=1000.000000 negative_attraction_constant=1.000000 repulsion_constant=1.000000 matter_distribution=CoreHalo type_diameter=50.000000 positive_ratio=0.500000 core_extra_negative_density=0.000000 batch_steps=2000 snapshots=4 output_dir=outputs

batch_jobs.cfg

@@ -0,0 +1,6 @@
+# Galaxy simulation batch jobs
+# One simulation per line. Copy/paste SIMCFG lines from terminal or menu export.
+# Keys:
+# simulation_type step smoothing_length interaction_rate nb_stars galaxy_diameter galaxy_thickness galaxies_distance stars_speed black_hole_mass negative_attraction_constant repulsion_constant matter_distribution type_diameter positive_ratio core_extra_negative_density camera_view batch_steps snapshots output_dir
+
+SIMCFG simulation_type=Galaxy step=0.001000 smoothing_length=1.000000 interaction_rate=0.050000 nb_stars=30000 galaxy_diameter=100.000000 galaxy_thickness=5.000000 galaxies_distance=75.000000 stars_speed=20.000000 black_hole_mass=1000.000000 negative_attraction_constant=1.000000 repulsion_constant=1.000000 matter_distribution=CoreHalo type_diameter=40.000000 positive_ratio=0.500000 core_extra_negative_density=0.000000 camera_view=top batch_steps=3000 snapshots=4 output_dir=outputs/run_001