Implement automatic batching for points, lines, shapes, and images/quads.

The above are batched together into a single draw call when called without other drawing calls in between, as long as the following criteria are met:

- The texture is the same.
- The primitive type is the same (points cannot be batched with non-points).
- The love.graphics state is the same (aside from the current color - i.e. setColor - and the transform state).
- The active shader’s uniform values are the same.

You can examine the ‘drawcalls’ field of love.graphics.getStats() to help determine if your code is allowing for optimum batching.

--HG--
branch : minor

src/modules/graphics/StreamBuffer.h

@@ -0,0 +1,77 @@
+/**
+ * Copyright (c) 2006-2016 LOVE Development Team
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ * 1. The origin of this software must not be misrepresented; you must not
+ *    claim that you wrote the original software. If you use this software
+ *    in a product, an acknowledgment in the product documentation would be
+ *    appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *    misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ **/
+
+#pragma once
+
+// LOVE
+#include "common/int.h"
+
+// C
+#include <cstddef>
+
+namespace love
+{
+namespace graphics
+{
+
+// TODO: This class will need to be changed significantly in the future to
+// accomodate non-client-side vertex/index data.
+class StreamBuffer
+{
+public:
+
+	enum Mode
+	{
+		MODE_VERTEX,
+		MODE_INDEX,
+	};
+
+	StreamBuffer(Mode mode, size_t size);
+	~StreamBuffer();
+
+	void *getData() const;
+	void *getOffsetData() const;
+
+	void incrementOffset(size_t amount);
+	void resetOffset();
+
+	void setSize(size_t size);
+
+	size_t getSize() const
+	{
+		return totalSize;
+	}
+
+	Mode getMode() const
+	{
+		return mode;
+	}
+
+private:
+
+	uint8 *data;
+	size_t offset;
+	size_t totalSize;
+	Mode mode;
+
+}; // StreamBuffer
+
+} // graphics
+} // love