[core] Use numeric_limits<>::max() for checking element groups

7 files changed, 28 insertions, 29 deletions

diff --git a/src/mbgl/renderer/circle_bucket.cpp b/src/mbgl/renderer/circle_bucket.cpp
index cb6ba7d458..9c1c5a6b44 100644
--- a/src/mbgl/renderer/circle_bucket.cpp
+++ b/src/mbgl/renderer/circle_bucket.cpp
@@ -31,6 +31,8 @@ bool CircleBucket::hasData() const {
 }
 
 void CircleBucket::addGeometry(const GeometryCollection& geometryCollection) {
+    constexpr const uint16_t vertexLength = 4;
+
     for (auto& circle : geometryCollection) {
         for(auto & geometry : circle) {
             auto x = geometry.x;
@@ -42,7 +44,7 @@ void CircleBucket::addGeometry(const GeometryCollection& geometryCollection) {
             if ((mode != MapMode::Still) &&
                 (x < 0 || x >= util::EXTENT || y < 0 || y >= util::EXTENT)) continue;
 
-            if (!segments.size() || segments.back().vertexLength + 4 > 65535) {
+            if (segments.back().vertexLength + vertexLength > std::numeric_limits<uint16_t>::max()) {
                 // Move to a new segments because the old one can't hold the geometry.
                 segments.emplace_back(vertices.size(), triangles.size());
             }
@@ -62,18 +64,15 @@ void CircleBucket::addGeometry(const GeometryCollection& geometryCollection) {
             vertices.emplace_back(x, y, -1, 1); // 4
 
             auto& segment = segments.back();
+            assert(segment.vertexLength <= std::numeric_limits<uint16_t>::max());
             uint16_t index = segment.vertexLength;
 
             // 1, 2, 3
             // 1, 4, 3
-            triangles.emplace_back(index,
-                                   static_cast<uint16_t>(index + 1),
-                                   static_cast<uint16_t>(index + 2));
-            triangles.emplace_back(index,
-                                   static_cast<uint16_t>(index + 3),
-                                   static_cast<uint16_t>(index + 2));
-
-            segment.vertexLength += 4;
+            triangles.emplace_back(index, index + 1, index + 2);
+            triangles.emplace_back(index, index + 3, index + 2);
+
+            segment.vertexLength += vertexLength;
             segment.primitiveLength += 2;
         }
     }
diff --git a/src/mbgl/renderer/circle_bucket.hpp b/src/mbgl/renderer/circle_bucket.hpp
index a682d423d6..494e64cc0f 100644
--- a/src/mbgl/renderer/circle_bucket.hpp
+++ b/src/mbgl/renderer/circle_bucket.hpp
@@ -22,7 +22,7 @@ public:
 
     std::vector<CircleVertex> vertices;
     std::vector<gl::Triangle> triangles;
-    std::vector<gl::Segment> segments;
+    std::vector<gl::Segment> segments { { 0, 0 } };
 
     optional<gl::VertexBuffer<CircleVertex>> vertexBuffer;
     optional<gl::IndexBuffer<gl::Triangle>> indexBuffer;
diff --git a/src/mbgl/renderer/fill_bucket.cpp b/src/mbgl/renderer/fill_bucket.cpp
index 2c69524c0d..86b3946f64 100644
--- a/src/mbgl/renderer/fill_bucket.cpp
+++ b/src/mbgl/renderer/fill_bucket.cpp
@@ -39,7 +39,7 @@ void FillBucket::addGeometry(const GeometryCollection& geometry) {
 
         for (const auto& ring : polygon) {
             totalVertices += ring.size();
-            if (totalVertices > 65535)
+            if (totalVertices > std::numeric_limits<uint16_t>::max())
                 throw GeometryTooLongException();
         }
 
@@ -51,21 +51,20 @@ void FillBucket::addGeometry(const GeometryCollection& geometry) {
             if (nVertices == 0)
                 continue;
 
-            if (lineSegments.empty() || lineSegments.back().vertexLength + nVertices > 65535) {
+            if (lineSegments.back().vertexLength + nVertices > std::numeric_limits<uint16_t>::max()) {
                 lineSegments.emplace_back(vertices.size(), lines.size());
             }
 
             auto& lineSegment = lineSegments.back();
+            assert(lineSegment.vertexLength <= std::numeric_limits<uint16_t>::max());
             uint16_t lineIndex = lineSegment.vertexLength;
 
             vertices.emplace_back(ring[0].x, ring[0].y);
-            lines.emplace_back(static_cast<uint16_t>(lineIndex + nVertices - 1),
-                               static_cast<uint16_t>(lineIndex));
+            lines.emplace_back(lineIndex + nVertices - 1, lineIndex);
 
             for (uint32_t i = 1; i < nVertices; i++) {
                 vertices.emplace_back(ring[i].x, ring[i].y);
-                lines.emplace_back(static_cast<uint16_t>(lineIndex + i - 1),
-                                   static_cast<uint16_t>(lineIndex + i));
+                lines.emplace_back(lineIndex + i - 1, lineIndex + i);
             }
 
             lineSegment.vertexLength += nVertices;
@@ -77,17 +76,18 @@ void FillBucket::addGeometry(const GeometryCollection& geometry) {
         std::size_t nIndicies = indices.size();
         assert(nIndicies % 3 == 0);
 
-        if (triangleSegments.empty() || triangleSegments.back().vertexLength + totalVertices > 65535) {
+        if (triangleSegments.back().vertexLength + totalVertices > std::numeric_limits<uint16_t>::max()) {
             triangleSegments.emplace_back(startVertices, triangles.size());
         }
 
         auto& triangleSegment = triangleSegments.back();
+        assert(triangleSegment.vertexLength <= std::numeric_limits<uint16_t>::max());
         uint16_t triangleIndex = triangleSegment.vertexLength;
 
         for (uint32_t i = 0; i < nIndicies; i += 3) {
-            triangles.emplace_back(static_cast<uint16_t>(triangleIndex + indices[i]),
-                                   static_cast<uint16_t>(triangleIndex + indices[i + 1]),
-                                   static_cast<uint16_t>(triangleIndex + indices[i + 2]));
+            triangles.emplace_back(triangleIndex + indices[i],
+                                   triangleIndex + indices[i + 1],
+                                   triangleIndex + indices[i + 2]);
         }
 
         triangleSegment.vertexLength += totalVertices;
diff --git a/src/mbgl/renderer/fill_bucket.hpp b/src/mbgl/renderer/fill_bucket.hpp
index 715b8e2745..58fa916f82 100644
--- a/src/mbgl/renderer/fill_bucket.hpp
+++ b/src/mbgl/renderer/fill_bucket.hpp
@@ -22,8 +22,8 @@ public:
     std::vector<FillVertex> vertices;
     std::vector<gl::Line> lines;
     std::vector<gl::Triangle> triangles;
-    std::vector<gl::Segment> lineSegments;
-    std::vector<gl::Segment> triangleSegments;
+    std::vector<gl::Segment> lineSegments { { 0, 0 } };
+    std::vector<gl::Segment> triangleSegments { { 0, 0 } };
 
     optional<gl::VertexBuffer<FillVertex>> vertexBuffer;
     optional<gl::IndexBuffer<gl::Line>> lineIndexBuffer;
diff --git a/src/mbgl/renderer/line_bucket.cpp b/src/mbgl/renderer/line_bucket.cpp
index 229b14d489..0298e174a1 100644
--- a/src/mbgl/renderer/line_bucket.cpp
+++ b/src/mbgl/renderer/line_bucket.cpp
@@ -348,17 +348,17 @@ void LineBucket::addGeometry(const GeometryCoordinates& coordinates) {
     const std::size_t endVertex = vertices.size();
     const std::size_t vertexCount = endVertex - startVertex;
 
-    if (segments.empty() || segments.back().vertexLength + vertexCount > 65535) {
+    if (segments.back().vertexLength + vertexCount > std::numeric_limits<uint16_t>::max()) {
+        // Move to a new group because the old one can't hold the geometry.
         segments.emplace_back(startVertex, triangles.size());
     }
 
     auto& segment = segments.back();
+    assert(segment.vertexLength <= std::numeric_limits<uint16_t>::max());
     uint16_t index = segment.vertexLength;
 
     for (const auto& triangle : triangleStore) {
-        triangles.emplace_back(static_cast<uint16_t>(index + triangle.a),
-                               static_cast<uint16_t>(index + triangle.b),
-                               static_cast<uint16_t>(index + triangle.c));
+        triangles.emplace_back(index + triangle.a, index + triangle.b, index + triangle.c);
     }
 
     segment.vertexLength += vertexCount;
diff --git a/src/mbgl/renderer/line_bucket.hpp b/src/mbgl/renderer/line_bucket.hpp
index 7b4c5f1b57..3ee142a70b 100644
--- a/src/mbgl/renderer/line_bucket.hpp
+++ b/src/mbgl/renderer/line_bucket.hpp
@@ -28,7 +28,7 @@ public:
 
     std::vector<LineVertex> vertices;
     std::vector<gl::Triangle> triangles;
-    std::vector<gl::Segment> segments;
+    std::vector<gl::Segment> segments { { 0, 0 } };
 
     optional<gl::VertexBuffer<LineVertex>> vertexBuffer;
     optional<gl::IndexBuffer<gl::Triangle>> indexBuffer;
diff --git a/src/mbgl/renderer/symbol_bucket.hpp b/src/mbgl/renderer/symbol_bucket.hpp
index a905e25363..881475e4a9 100644
--- a/src/mbgl/renderer/symbol_bucket.hpp
+++ b/src/mbgl/renderer/symbol_bucket.hpp
@@ -36,7 +36,7 @@ public:
     struct TextBuffer {
         std::vector<SymbolVertex> vertices;
         std::vector<gl::Triangle> triangles;
-        std::vector<gl::Segment> segments;
+        std::vector<gl::Segment> segments { { 0, 0 } };
 
         optional<gl::VertexBuffer<SymbolVertex>> vertexBuffer;
         optional<gl::IndexBuffer<gl::Triangle>> indexBuffer;
@@ -45,7 +45,7 @@ public:
     struct IconBuffer {
         std::vector<SymbolVertex> vertices;
         std::vector<gl::Triangle> triangles;
-        std::vector<gl::Segment> segments;
+        std::vector<gl::Segment> segments { { 0, 0 } };
 
         optional<gl::VertexBuffer<SymbolVertex>> vertexBuffer;
         optional<gl::IndexBuffer<gl::Triangle>> indexBuffer;