Added support for PCB layer types and pad clearance overrides

src/footprint/data.rs

@@ -165,6 +165,8 @@ pub enum Element {
     At(At),
     /// 3D model information
     Model(Model),
+    /// Clearance override for module
+    Clearance(f64),
     /// is the module locked
     Locked,
 }
@@ -186,6 +188,7 @@ impl BoundingBox for Element {
             Element::Model(_) |
             Element::Attr(_) |
             Element::SolderMaskMargin(_) |
+            Element::Clearance(_) |
             Element::Tags(_) |
             Element::Locked |
             Element::TStamp(_) => Bound::default(),
@@ -211,6 +214,7 @@ impl Named for Element {
             Element::Model(_) => "Model",
             Element::TStamp(_) => "Tstamp",
             Element::SolderMaskMargin(_) => "SolderMaskMargin",
+            Element::Clearance(_) |
             Element::Tags(_) => "Tags",
             Element::Attr(_) => "Attr",
             Element::Locked => "Locked",

src/footprint/de.rs

@@ -390,6 +390,7 @@ impl FromSexp for Element {
                     "path" => wrap(s, parse_string_element, Element::Path),
                     "at" => wrap(s, from_sexp, Element::At),
                     "model" => wrap(s, from_sexp, Element::Model),
+                    "clearance" => wrap(s, parse_float_element, Element::Clearance),
                     _ => Err(format!("unknown element in module: {}", name).into()),
                 }
             }

src/footprint/ser.rs

@@ -35,6 +35,7 @@ impl IntoSexp for Element {
             Element::Path(ref p) => ("path", p).into(),
             Element::At(ref p) => p.into_sexp(),
             Element::Model(ref p) => p.into_sexp(),
+            Element::Clearance(ref s) => ("clearance", s).into(),
             Element::Locked => "locked".into(),
         }
     }

src/layout/data.rs

@@ -233,6 +233,12 @@ pub struct Layer {
 pub enum LayerType {
     /// signal layer
     Signal,
+    /// power layer
+    Power,
+    /// mixed layer
+    Mixed,
+    /// jumper layer
+    Jumper,
     /// user layer
     User,
 }

src/layout/de.rs

@@ -161,6 +161,9 @@ impl FromSexp for LayerType {
         let x = s.string()?;
         match &x[..] {
             "signal" => Ok(LayerType::Signal),
+            "power" => Ok(LayerType::Power),
+            "mixed" => Ok(LayerType::Mixed),
+            "jumper" => Ok(LayerType::Jumper),
             "user" => Ok(LayerType::User),
             _ => Err(format!("unknown layertype {} in {}", x, s).into()),
         }

src/layout/ser.rs

@@ -231,6 +231,9 @@ impl fmt::Display for LayerType {
     fn fmt(&self, f: &mut fmt::Formatter) -> result::Result<(), fmt::Error> {
         let s = match *self {
             LayerType::Signal => "signal",
+            LayerType::Power => "power",
+            LayerType::Mixed => "mixed",
+            LayerType::Jumper => "jumper",
             LayerType::User => "user",
         };
         write!(f, "{}", s)