1 files changed, 61 insertions, 0 deletions
diff --git a/src/mbgl/gl/vao.cpp b/src/mbgl/gl/vao.cpp
new file mode 100644
index 0000000000..527dd214fb
--- /dev/null
+++ b/src/mbgl/gl/vao.cpp
@@ -0,0 +1,61 @@
+#include <mbgl/gl/vao.hpp>
+#include <mbgl/gl/vertex_array.hpp>
+#include <mbgl/platform/log.hpp>
+#include <mbgl/util/string.hpp>
+#include <mbgl/gl/gl.hpp>
+
+namespace mbgl {
+
+VertexArrayObject::VertexArrayObject() {
+}
+
+VertexArrayObject::~VertexArrayObject() = default;
+
+void VertexArrayObject::bindVertexArrayObject(gl::Context& context) {
+    if (!gl::GenVertexArrays || !gl::BindVertexArray) {
+        static bool reported = false;
+        if (!reported) {
+            Log::Warning(Event::OpenGL, "Not using Vertex Array Objects");
+            reported = true;
+        }
+        return;
+    }
+
+    if (!vertexArray) {
+        vertexArray = context.createVertexArray();
+        context.vertexBuffer.setDirty();
+        context.elementBuffer.setDirty();
+    }
+
+    context.vertexArrayObject = *vertexArray;
+}
+
+void VertexArrayObject::verifyBinding(Shader& shader,
+                                      gl::BufferID vertexBuffer,
+                                      gl::BufferID elementsBuffer,
+                                      int8_t* offset) {
+    if (bound_shader != shader.getID()) {
+        throw std::runtime_error(std::string("trying to rebind VAO to another shader from " +
+                                             util::toString(bound_shader) + "(" + bound_shader_name + ") to " +
+                                             util::toString(shader.getID()) + "(" + shader.name + ")" ));
+    } else if (bound_offset != offset) {
+        throw std::runtime_error("trying to bind VAO to another offset");
+    } else if (bound_vertex_buffer != vertexBuffer) {
+        throw std::runtime_error("trying to bind VAO to another vertex buffer");
+    } else if (bound_elements_buffer != elementsBuffer) {
+        throw std::runtime_error("trying to bind VAO to another elements buffer");
+    }
+}
+
+void VertexArrayObject::storeBinding(Shader& shader,
+                                     gl::BufferID vertexBuffer,
+                                     gl::BufferID elementsBuffer,
+                                     int8_t* offset) {
+    bound_shader = shader.getID();
+    bound_shader_name = shader.name;
+    bound_offset = offset;
+    bound_vertex_buffer = vertexBuffer;
+    bound_elements_buffer = elementsBuffer;
+}
+
+} // namespace mbgl