HPGL: change velocity to int (#286)

- write -f hpgl now only accepts int for -velocity/--vs
- HPGL outputs VS command with int value only

Fixes# 255

CHANGELOG.md

@@ -2,12 +2,11 @@
 
 #### 1.7 (UNRELEASED)
 
-**Important**: for a normal installation, *vpype* must now be installed/updated with the following command:
+**Important**: for a regular installation, *vpype* must now be installed/updated with the following command:
 ```
 pip install -U vpype[all]
 ```
 
-
 New features and improvements:
 * The viewer (`show` command) and its dependencies is no longer required and is installed only if the `all` extra is provided to `pip`:
   ```
@@ -20,6 +19,7 @@ Bug fixes:
 * Fixed systematic crash when using the Windows installer (#285)
 * Fixed an issue where `read` would crash with empty `<polygon>` tags and similar degenerate geometries (#260)
 * Fixed an issue where `linesimplify` would skip layers containing a single line (#280)
+* Fixed an issue where floating point value could be generated for HPGL VS commands (#286)
 
 Other changes:
 * Updated to Click 8.0.1 (#282) 

vpype/io.py

@@ -494,7 +494,7 @@ def write_hpgl(
     landscape: bool,
     center: bool,
     device: Optional[str],
-    velocity: Optional[float],
+    velocity: Optional[int],
     quiet: bool = False,
 ) -> None:
     """Create a HPGL file from the :class:`Document` instance.
@@ -608,7 +608,7 @@ def complex_to_str(p: complex) -> str:
 
     output.write("IN;DF;")
     if velocity is not None:
-        output.write(f"VS{velocity};")
+        output.write(f"VS{int(velocity)};")
     if paper_config.set_ps is not None:
         output.write(f"PS{int(paper_config.set_ps)};")
 

vpype_cli/write.py

@@ -152,7 +152,7 @@
 @click.option(
     "-vs",
     "--velocity",
-    type=float,
+    type=int,
     help="[HPGL only] Emit a VS command with the provided value.",
 )
 @click.option(