diff --git a/cmd/mtdbconverter/sqlite.go b/cmd/mtdbconverter/sqlite.go
index 55f5b73..1c12c94 100644
--- a/cmd/mtdbconverter/sqlite.go
+++ b/cmd/mtdbconverter/sqlite.go
@@ -15,10 +15,10 @@ import (
 )
 
 const (
-	createSql = "CREATE TABLE blocks (pos INT NOT NULL PRIMARY KEY, data BLOB)"
-	insertSql = "INSERT INTO blocks (pos, data) VALUES (?, ?)"
-	deleteSql = "DELETE FROM blocks"
-	selectSql = "SELECT pos, data FROM blocks"
+	createSQL = "CREATE TABLE blocks (pos INT NOT NULL PRIMARY KEY, data BLOB)"
+	insertSQL = "INSERT INTO blocks (pos, data) VALUES (?, ?)"
+	deleteSQL = "DELETE FROM blocks"
+	selectSQL = "SELECT pos, data FROM blocks"
 )
 
 var ErrDatabaseNotExists = errors.New("Database does not exists.")
@@ -58,19 +58,19 @@ func NewSQLiteBlockConsumer(
 	}
 
 	if createNew {
-		if _, err = db.Exec(createSql); err != nil {
+		if _, err = db.Exec(createSQL); err != nil {
 			db.Close()
 			return
 		}
 	} else {
-		if _, err = db.Exec(deleteSql); err != nil {
+		if _, err = db.Exec(deleteSQL); err != nil {
 			db.Close()
 			return
 		}
 	}
 
 	var insertStmt *sql.Stmt
-	if insertStmt, err = db.Prepare(insertSql); err != nil {
+	if insertStmt, err = db.Prepare(insertSQL); err != nil {
 		db.Close()
 		return
 	}
@@ -136,7 +136,7 @@ func NewSQLiteBlockProducer(
 	}
 
 	var rows *sql.Rows
-	if rows, err = db.Query(selectSql); err != nil {
+	if rows, err = db.Query(selectSQL); err != nil {
 		db.Close()
 		return
 	}
diff --git a/cmd/mtredisalize/sqlite.go b/cmd/mtredisalize/sqlite.go
index f86a286..b8b63e8 100644
--- a/cmd/mtredisalize/sqlite.go
+++ b/cmd/mtredisalize/sqlite.go
@@ -123,12 +123,12 @@ func NewSqliteBackend(
 	return
 }
 
-func (sb *SqliteBackend) buildCoverage() (err error) {
+func (sqlb *SqliteBackend) buildCoverage() (err error) {
 	log.Println("INFO: Start building coverage index (this may take some time)...")
-	sb.coverage = common.NewCoverage3D()
+	sqlb.coverage = common.NewCoverage3D()
 
 	var rows *sql.Rows
-	if rows, err = sb.keysStmt.Query(); err != nil {
+	if rows, err = sqlb.keysStmt.Query(); err != nil {
 		return
 	}
 	defer rows.Close()
@@ -138,7 +138,7 @@ func (sb *SqliteBackend) buildCoverage() (err error) {
 		if err = rows.Scan(&key); err != nil {
 			return
 		}
-		sb.coverage.Insert(common.PlainToCoord(key))
+		sqlb.coverage.Insert(common.PlainToCoord(key))
 	}
 	err = rows.Err()
 	log.Println("INFO: Finished building coverage index.")
diff --git a/common/block.go b/common/block.go
index 9489a07..8efae8c 100644
--- a/common/block.go
+++ b/common/block.go
@@ -53,8 +53,8 @@ type (
 		Version     byte
 		Transparent bool
 		MapContent  []byte
-		AirId       int32
-		IgnoreId    int32
+		AirID       int32
+		IgnoreID    int32
 		IndexMap    map[int32]int32
 	}
 )
@@ -196,7 +196,7 @@ func NewDecodedBlock(data []byte, colors *Colors) (db *DecodedBlock, err error)
 	}
 	offset += 4
 
-	airId, ignoreId := int32(-1), int32(-1)
+	airID, ignoreID := int32(-1), int32(-1)
 	indexMap := make(map[int32]int32)
 	var transparent bool
 	if version >= 22 {
@@ -216,7 +216,7 @@ func NewDecodedBlock(data []byte, colors *Colors) (db *DecodedBlock, err error)
 				log.Println(outOfBounds)
 				break
 			}
-			nodeId := int32(binary.BigEndian.Uint16(data[offset:]))
+			nodeID := int32(binary.BigEndian.Uint16(data[offset:]))
 			offset += 2
 			if offset+1 >= dataLen {
 				log.Println(outOfBounds)
@@ -232,12 +232,12 @@ func NewDecodedBlock(data []byte, colors *Colors) (db *DecodedBlock, err error)
 			offset += nameLen
 			switch name {
 			case "air":
-				airId = nodeId
+				airID = nodeID
 			case "ignore":
-				ignoreId = nodeId
+				ignoreID = nodeID
 			default:
 				if index, found := colors.NameIndex[name]; found {
-					indexMap[nodeId] = index
+					indexMap[nodeID] = index
 					if !transparent && colors.IsTransparent(index) {
 						transparent = true
 					}
@@ -252,8 +252,8 @@ func NewDecodedBlock(data []byte, colors *Colors) (db *DecodedBlock, err error)
 		Version:     version,
 		Transparent: transparent,
 		MapContent:  mapContent,
-		AirId:       airId,
-		IgnoreId:    ignoreId,
+		AirID:       airID,
+		IgnoreID:    ignoreID,
 		IndexMap:    indexMap}
 
 	return
@@ -274,7 +274,7 @@ func logMissing(name string) {
 }
 
 func (db *DecodedBlock) AirOnly() bool {
-	return db.AirId != -1 && len(db.IndexMap) == 0
+	return db.AirID != -1 && len(db.IndexMap) == 0
 }
 
 func (db *DecodedBlock) Content(x, y, z int) (content int32, found bool) {
@@ -293,7 +293,7 @@ func (db *DecodedBlock) Content(x, y, z int) (content int32, found bool) {
 	default:
 		return
 	}
-	if content != db.AirId && content != db.IgnoreId {
+	if content != db.AirID && content != db.IgnoreID {
 		content, found = db.IndexMap[content]
 	}
 	return
diff --git a/common/colors.go b/common/colors.go
index c9a6bdd..9c18873 100644
--- a/common/colors.go
+++ b/common/colors.go
@@ -15,7 +15,8 @@ import (
 	"strings"
 )
 
-// Dim transparent 2% every node.
+// DefaultTransparentDim sets the default dimming
+// factor of transparent nodes to 2%.
 const DefaultTransparentDim = 2.0 / 100.0
 
 type Colors struct {
diff --git a/common/coords.go b/common/coords.go
index a09bde1..6aa42fd 100644
--- a/common/coords.go
+++ b/common/coords.go
@@ -271,34 +271,34 @@ func unsetbits(p uint8, v int64) int64 {
 
 func BigMin(minz, maxz, zcode int64) int64 {
 	const (
-		_001_ = 1
-		_010_ = 2
-		_011_ = 2 | 1
-		_100_ = 4
-		_101_ = 4 | 1
+		b001 = 1
+		b010 = 2
+		b011 = 2 | 1
+		b100 = 4
+		b101 = 4 | 1
 	)
 	bigmin := maxz
 	pos := msb
 	for m := int64(1) << msb; m != 0; m >>= 1 {
 		var v uint8
 		if zcode&m == m {
-			v = _100_
+			v = b100
 		}
 		if minz&m == m {
-			v |= _010_
+			v |= b010
 		}
 		if maxz&m == m {
-			v |= _001_
+			v |= b001
 		}
 		switch v {
-		case _001_:
+		case b001:
 			bigmin = unsetbits(pos, minz)
 			maxz = setbits(pos, maxz)
-		case _011_:
+		case b011:
 			return minz
-		case _100_:
+		case b100:
 			return bigmin
-		case _101_:
+		case b101:
 			minz = unsetbits(pos, minz)
 		}
 		pos--
diff --git a/common/renderer.go b/common/renderer.go
index 1912ac6..89410c4 100644
--- a/common/renderer.go
+++ b/common/renderer.go
@@ -292,8 +292,9 @@ func areasContain(areas []Area, x, z int16) bool {
 	return false
 }
 
-// Greedy algorithm to figure out a list of disjunct areas
-// of free regions in the domain to the (x, z) block plane.
+// UncoveredAreas implements a greedy algorithm to figure out
+// a list of disjunct areas of free regions in the domain
+// to the (x, z) block plane.
 // oldAreas are searched and found free areas are appended
 // to newAreas which ist return.
 // This is useful to spatial query only blocks from db