diff --git a/.gitignore b/.gitignore
index 10044a1..2270798 100755
--- a/.gitignore
+++ b/.gitignore
@@ -276,3 +276,4 @@ __pycache__/
*.mp4
src/result.mp4
+src/main
diff --git a/README.md b/README.md
index 1a6c728..c55dcb5 100755
--- a/README.md
+++ b/README.md
@@ -1,175 +1,8 @@
-# MPM2D
+# SDF-based collision detection with MPM2D
+I integrate SDF-based collision detection into an MPM simulator.
-2D implementation of the Material Point Method.
-
-
-
-## Sections
-- [Overview](#Overview)
-- [Dependencies](#Dependencies)
-- [Code structure](#Code-structure)
-- [Implementation](#Implementation)
-- [Options](#Options)
-
+The SDF algorithm is inspired by Yuanming Hu's [Taichi](https://github.com/yuanming-hu/taichi).
+And the MPM algorithm is from [Elias-Gu's MPM2D](https://github.com/Elias-Gu/MPM2D).
-## Overview
-C++ implementation of the Material Point Method.
-
-The [Material Point Method](https://www.seas.upenn.edu/~cffjiang/research/mpmcourse/mpmcourse.pdf) is a numerical technique used to simulate the behavior of continuum materials.
-
-The continuum body is described by a number a Lagrangian elements : the material points.
-Kinematic equations are solved on the material points
-The material points are surrounded by a background Eulerian grid where the dynamic equations are solved.
-
-It can be summarize in 4 main steps:
-1. Transfer data from particles de grid nodes
-2. Update node state (apply forces)
-3. Transfer data from grid nodes to particles
-4. Update particles state
-
-
-## Dependencies
-The following libraries are includes in the `ext/` directory:
-- [OpenGL and GLFW](https://www.glfw.org/)
- - Visual.
-- [Poisson Generator](https://github.com/corporateshark/poisson-disk-generator)
- - Initialize particle position.
-- [Algebra](https://github.com/Elias-Gu/MPM2D/tree/master/MPM2D/ext/Algebra)
- - My own 2D linear algebra library.
-- [Eigen](http://eigen.tuxfamily.org/index.php?title=Main_Page)
- - Alternatively, `Eigen` can be used to replace `Algebra`, but it is not as fast. The source code is in `ext/Eigen/MPM2D/src/` (not updated).
-
-The followings are optional dependencies :
-- [ffmpeg](https://www.ffmpeg.org/)
- - Output .mp4 videos.
-- [OpenMP](https://www.openmp.org/)
- - Parallel computing.
-
-
-## Code structure
-The code, located in `src/`, is structured as following:
-- `main.cpp`: OpenGL context. Run simulation.
-- `solver.h` and `solver.cpp`: MPM algorithm functions (transfers and updates). Rendering and WriteToFile.
-- `node.h` and `node.cpp`: Class for grid nodes.
-- `border.h` and `border.cpp`: Class for 2D linear borders. Collision and Friction.
-- `particle.h` and `particle.cpp`: Class and subclasses for particles and materials. Constitutive model and deformation functions.
-- `constants.h`: Option control and global constants.
-
-
-## Implementation
-
-#### Characteristics:
-Here are the main features of this implementation:
-- Sand, Water, Snow and purely elastic simulatiosn already implemented
-- 2D.
-- Affine-Particle-in-Cell ([APIC](http://www.math.ucla.edu/~jteran/papers/JSSTS15.pdf)) transfer type.
-- B-Spline Quadratic or Cubic interpolation functions (Quadratic is faster, but not as precise).
-- Node forces are updated with an explicit method.
-- The domain has to be a convex geometry (for collision detection).
-
-#### Add material type:
-It is easy to add a new type of material. In `particle.h` and `particle.cpp`, create a new subclasse of `Particle`. Beside constructors, the subclass must contain the following functions:
-- In `particle.h`:
-```C++
-static std::vector InitializeParticles() {
- // Define initial particle mass, volume, position, velocity and acceleration
- std::vector outParticles;
- // ...
- return outParticles;
-}
-```
-```C++
-static std::vector AddParticles() {
- // Define mass, volume, position, velocity and acceleration of particles to add during the simulation
- std::vector outParticles;
- // ...
- return outParticles;
-}
-```
-
-
-- In `particle.cpp`:
-```C++
-void NewMaterial::ConstitutiveModel() {
- // Update Ap (pre-update deformation gradient)
-}
-```
-
-```C++
-void NewMaterial::UpdateDeformation(const Matrix2f& T) {
- // Update deformation gradient.
- // T is the sum of the close node velocity gradients.
- // Elasticity, Plasticity functions (return-mapping, hardening) ...
-}
-```
-```C++
-void NewMaterial::DrawParticle() {
- // OpenGL output of particle points
-}
-```
-
-#### Change domain geometry:
-The shape of the domain can be changed, but is has to follow this rules:
-- It has to be [convex](https://www.easycalculation.com/maths-dictionary/images/convex-nonconvex-set.png).
-- It has to be included in [`CUB` ; `X_GRID - CUB`] x [`CUB` ; `Y_GRID - CUB`], where `CUB` is the range of the interpolation function (2 for Cubic, 1.5 for Quadratic).
-- Borders have to be straight lines.
-
-To modify the domain, in `border.h`, use the `InitializeBorders` static function:
-```C++
-static std::vector InitializeBorders() {
- std::vector outBorders;
- std::vector Corners;
-
- // New border line
- Corners.push_back(Vector2f(X1, Y1)); // First point
- Corners.push_back(Vector2f(X2, Y2)); // Second point
- // type can be [1](sticky), [2](Separating) or [3](Sliding)
- // normal has to be oriented inside the domain and normalized
- outBorders.push_back(Border(type, normal, Corners));
- Corners.clear();
-
- // Add other border
-
- return outBorders;
-}
-```
-
-
-## Options
-Here is a list of different options available. They can be modify in the `constants.h` file.
-- Grid:
-```C++
-// Size of the domain
-const static int X_GRID = 128;
-const static int Y_GRID = 64;
-```
-- Particle:
-```C++
-// Select Particle subclass (material type). [Water], [DrySand], [Snow], [Elastic]
-#define Material NewMaterial
-```
-
-- Transfer particles <-> grid:
-```C++
-// Interpolation type: [1] Cubic - [2] Quadratic
-#define INTERPOLATION 1
-// Time-step (typically about 1e-4)
-const static float DT = 0.0001f;
-```
-- Output (outputs will be generated in the `out/` directory):
-```C++
-// Generate a .mp4 of the OpenGL window
-#define RECORD_VIDEO true
-// Generate a .ply file with node coordinates
-#define WRITE_TO_FILE false
-// Draw nodes (active nodes have a different color)
-#define DRAW_NODES false // not recommended (slow)
-```
-
-
-### In progress
-I am working on a more complete version that will include:
-- 3D
-- Sparse Grid parallelisme (CUDA - OpenACC or OpenMP)
-- Implicit grid update
-- Other transfer schemes (MLS-MPM, PolyPIC)
\ No newline at end of file
+# Result
+