Change readers.ply output for integers with precision set (#2422)

* Don't write ints using fixed precision.

* Test for issue 2421.

Close #2421

io/PlyWriter.cpp

@@ -153,11 +153,6 @@ void PlyWriter::ready(PointTableRef table)
             " points supported.");
 
     m_stream = Utils::createFile(m_filename, true);
-    if (m_format == Format::Ascii && m_precisionArg->set())
-    {
-        *m_stream << std::fixed;
-        m_stream->precision(m_precision);
-    }
     writeHeader(table.layout());
 }
 
@@ -174,6 +169,14 @@ void PlyWriter::writeValue(PointRef& point, Dimension::Id dim,
     if (m_format == Format::Ascii)
     {
         double d = point.getFieldAs<double>(dim);
+        if (m_precisionArg->set() &&
+            Dimension::base(type) == Dimension::BaseType::Floating)
+        {
+            *m_stream << std::fixed;
+            m_stream->precision(m_precision);
+        }
+        else
+            m_stream->unsetf(std::ios_base::fixed);
         *m_stream << d;
     }
     else if (m_format == Format::BinaryLe)

test/data/ply/issue_2421.ply

@@ -0,0 +1,10 @@
+ply
+format ascii 1.0
+comment Generated by PDAL
+element vertex 1
+property float64 x
+property float64 y
+property float64 z
+property int32 i
+end_header
+1.23457 12345.67890 1234567890.12345 12345

test/unit/io/PlyWriterTest.cpp

@@ -156,4 +156,42 @@ TEST(PlyWriter, precisionException)
     EXPECT_THROW(writer.prepare(table), pdal_error);
 }
 
+// Make sure we don't write ints as floats.
+TEST(PlyWriter, issue_2421)
+{
+    std::string outfile(Support::temppath("out.ply"));
+    std::string referenceFile(Support::datapath("ply/issue_2421.ply"));
+
+    FileUtils::deleteFile(outfile);
+
+    PointTable t;
+
+    t.layout()->registerDim(Dimension::Id::X);
+    t.layout()->registerDim(Dimension::Id::Y);
+    t.layout()->registerDim(Dimension::Id::Z);
+    Dimension::Id iid = t.layout()->assignDim("I", Dimension::Type::Signed32);
+
+    PointViewPtr v(new PointView(t));
+    v->setField(Dimension::Id::X, 0, 1.23456789012345);
+    v->setField(Dimension::Id::Y, 0, 12345.6789012345);
+    v->setField(Dimension::Id::Z, 0, 1234567890.12345);
+    v->setField(iid, 0, 12345);
+
+    BufferReader r;
+    r.addView(v);
+
+    PlyWriter w;
+    Options wo;
+    wo.add("filename", outfile);
+    wo.add("storage_mode", "ascii");
+    wo.add("precision", 5);
+    w.setInput(r);
+    w.setOptions(wo);
+
+    w.prepare(t);
+    w.execute(t);
+
+    EXPECT_TRUE(Support::compare_text_files(outfile, referenceFile));
+}
+
 } // namespace pdal