1 files changed, 76 insertions, 0 deletions
diff --git a/src/mbgl/gl/draw_mode.hpp b/src/mbgl/gl/draw_mode.hpp
new file mode 100644
index 0000000000..ab86d5e469
--- /dev/null
+++ b/src/mbgl/gl/draw_mode.hpp
@@ -0,0 +1,76 @@
+#pragma once
+
+#include <mbgl/gl/primitives.hpp>
+#include <mbgl/util/variant.hpp>
+
+#include <cassert>
+
+namespace mbgl {
+namespace gl {
+
+class Points {
+public:
+    using Primitive = Point;
+    static constexpr std::size_t bufferGroupSize = 1;
+
+    explicit Points(float pointSize_) : pointSize(pointSize_) {}
+
+    float pointSize;
+};
+
+class Lines {
+public:
+    using Primitive = Line;
+    static constexpr std::size_t bufferGroupSize = 2;
+
+    explicit Lines(float lineWidth_) : lineWidth(lineWidth_) {
+        assert(lineWidth > 0);
+    }
+
+    float lineWidth;
+};
+
+class LineStrip {
+public:
+    // LineStrip is a form of "Line" rendering, but the element buffer
+    // cannot be grouped into logical elements beyond a single Point.
+    using Primitive = Line;
+    static constexpr std::size_t bufferGroupSize = 1;
+
+    explicit LineStrip(float lineWidth_) : lineWidth(lineWidth_) {
+        assert(lineWidth > 0);
+    }
+
+    float lineWidth;
+};
+
+class Triangles {
+public:
+    using Primitive = Triangle;
+    static constexpr std::size_t bufferGroupSize = 3;
+};
+
+class TriangleStrip {
+public:
+    // TriangleStrip is a form of "Triangle" rendering, but the element buffer
+    // cannot be grouped into logical elements beyond a single Point.
+    using Primitive = Triangle;
+    static constexpr std::size_t bufferGroupSize = 1;
+};
+
+// Special draw mode for use with VertexVector<Indexed, Vertex>, in which
+// case the true draw mode is denoted by the IndexVector type.
+class Indexed {
+public:
+    static constexpr std::size_t bufferGroupSize = 1;
+};
+
+using DrawMode = variant<
+    Points,
+    Lines,
+    LineStrip,
+    Triangles,
+    TriangleStrip>;
+
+} // namespace gl
+} // namespace mbgl