Update README.md

README.md

@@ -120,10 +120,19 @@ Next, follow the platform specific instructions.
 1.  Install build dependencies
     ``` bash
     sudo apt update
-    sudo apt install libxml2-dev libxrandr-dev libxinerama-dev \
+    sudo apt install build-essential libssl-dev \ 
+                     libxml2-dev libxrandr-dev libxinerama-dev \
                      libxcursor-dev libxi-dev libglu1-mesa-dev \
                      freeglut3-dev mesa-common-dev gcc-10 g++-10
     ```
+    If your cmake version is less than 3.18, you will need to update it
+    as well
+    ``` bash
+    cmake --version
+      3.16 # default on Ubunte 20.04 LTS
+    # if pip is present
+    pip install --update cmake
+    ```
 2.  Add GCC10 as alternative to GCC and select it:
     ``` bash
     sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 10
@@ -163,14 +172,6 @@ their Windows machine and use X11-forwarding to display the GUI.
     export LIBGL_ALWAYS_INDIRECT=0
     ```
 
------
-:warning: Older versions required manually enforcing OpenGL versions using :warning:
-```bash
-export MESA_GL_VERSION_OVERRIDE=3.3
-```
-:warning: in newer versions this will cause failures. :warning:
------
-
 ## MacOS
 
 Please use a recent version of Clang, as installed by brew for example.