framework/opengl/gluDrawUtil.hpp

#ifndef _GLUDRAWUTIL_HPP
#define _GLUDRAWUTIL_HPP
/*-------------------------------------------------------------------------
 * drawElements Quality Program OpenGL Utilities
 * ---------------------------------------------
 *
 * Copyright 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *//*!
 * \file
 * \brief Draw call utilities.
 *
 * Draw call utilities provide an abstraction for commonly used draw calls.
 * The objective of that abstraction is to allow moving data to buffers
 * and state to VAOs automatically if target context doesn't support
 * user pointers or default VAOs.
 *//*--------------------------------------------------------------------*/

#include "gluDefs.hpp"

#include <string>

namespace glu
{

class RenderContext;

enum VertexComponentType
{
	// Standard types: all conversion types apply.
	VTX_COMP_UNSIGNED_INT8		= 0,
	VTX_COMP_UNSIGNED_INT16,
	VTX_COMP_UNSIGNED_INT32,
	VTX_COMP_SIGNED_INT8,
	VTX_COMP_SIGNED_INT16,
	VTX_COMP_SIGNED_INT32,

	// Special types: only CONVERT_NONE is allowed.
	VTX_COMP_FIXED,
	VTX_COMP_HALF_FLOAT,
	VTX_COMP_FLOAT,

	VTX_COMP_TYPE_LAST
};

enum VertexComponentConversion
{
	VTX_COMP_CONVERT_NONE = 0,				//!< No conversion: integer types, or floating-point values.
	VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT,	//!< Normalize integers to range [0,1] or [-1,1] depending on type.
	VTX_COMP_CONVERT_CAST_TO_FLOAT,			//!< Convert to floating-point directly.

	VTX_COMP_CONVERT_LAST
};

enum IndexType
{
	INDEXTYPE_UINT8,
	INDEXTYPE_UINT16,
	INDEXTYPE_UINT32,

	INDEXTYPE_LAST
};

enum PrimitiveType
{
	PRIMITIVETYPE_TRIANGLES = 0,
	PRIMITIVETYPE_TRIANGLE_STRIP,
	PRIMITIVETYPE_TRIANGLE_FAN,

	PRIMITIVETYPE_LINES,
	PRIMITIVETYPE_LINE_STRIP,
	PRIMITIVETYPE_LINE_LOOP,

	PRIMITIVETYPE_POINTS,

	PRIMITIVETYPE_PATCHES,

	PRIMITIVETYPE_LAST
};

struct BindingPoint
{
	enum Type
	{
		TYPE_LOCATION = 0,			//!< Binding by numeric location.
		TYPE_NAME,					//!< Binding by input name.

		TYPE_LAST
	};

	Type			type;			//!< Binding type (name or location).
	std::string		name;			//!< Input name, or empty if is not binding by name.
	int				location;		//!< Input location, or offset to named location if binding by name.

				BindingPoint (void)											: type(TYPE_LAST), location (0) {}
	explicit	BindingPoint (int location_)								: type(TYPE_LOCATION), location(location_) {}
	explicit	BindingPoint (const std::string& name_, int location_ = 0)	: type(TYPE_NAME), name(name_), location(location_) {}
};

struct VertexArrayPointer
{
	VertexComponentType			componentType;	//!< Component type.
	VertexComponentConversion	convert;		//!< Component conversion type.
	int							numComponents;	//!< Number of components per element.
	int							numElements;	//!< Number of elements in total.
	int							stride;			//!< Element stride.

	const void*					data;			//!< Data pointer.

	VertexArrayPointer (VertexComponentType componentType_, VertexComponentConversion convert_, int numComponents_, int numElements_, int stride_, const void* data_)
		: componentType	(componentType_)
		, convert		(convert_)
		, numComponents	(numComponents_)
		, numElements	(numElements_)
		, stride		(stride_)
		, data			(data_)
	{
	}

	VertexArrayPointer (void)
		: componentType	(VTX_COMP_TYPE_LAST)
		, convert		(VTX_COMP_CONVERT_LAST)
		, numComponents	(0)
		, numElements	(0)
		, stride		(0)
		, data			(0)
	{
	}
} DE_WARN_UNUSED_TYPE;

struct VertexArrayBinding
{
	BindingPoint		binding;
	VertexArrayPointer	pointer;

	VertexArrayBinding (const BindingPoint& binding_, const VertexArrayPointer& pointer_)
		: binding	(binding_)
		, pointer	(pointer_)
	{
	}

	VertexArrayBinding (void)
	{
	}
} DE_WARN_UNUSED_TYPE;

struct PrimitiveList
{
	PrimitiveType		type;			//!< Primitive type.
	int					numElements;	//!< Number of elements to be drawn.
	IndexType			indexType;		//!< Index type or INDEXTYPE_LAST if not used
	const void*			indices;		//!< Index list or DE_NULL if not used.

	PrimitiveList (PrimitiveType type_, int numElements_)
		: type			(type_)
		, numElements	(numElements_)
		, indexType		(INDEXTYPE_LAST)
		, indices		(0)
	{
	}

	PrimitiveList (PrimitiveType type_, int numElements_, IndexType indexType_, const void* indices_)
		: type			(type_)
		, numElements	(numElements_)
		, indexType		(indexType_)
		, indices		(indices_)
	{
	}

	PrimitiveList (void)
		: type			(PRIMITIVETYPE_LAST)
		, numElements	(0)
		, indexType		(INDEXTYPE_LAST)
		, indices		(0)
	{
	}
} DE_WARN_UNUSED_TYPE;

class DrawUtilCallback
{
public:
	virtual void	beforeDrawCall	(void) { }
	virtual void	afterDrawCall	(void) { }
};

void	draw					(const RenderContext& context, deUint32 program, int numVertexArrays, const VertexArrayBinding* vertexArrays, const PrimitiveList& primitives, DrawUtilCallback* callback = DE_NULL);

void	drawFromUserPointers	(const RenderContext& context, deUint32 program, int numVertexArrays, const VertexArrayBinding* vertexArrays, const PrimitiveList& primitives, DrawUtilCallback* callback = DE_NULL);
void	drawFromBuffers			(const RenderContext& context, deUint32 program, int numVertexArrays, const VertexArrayBinding* vertexArrays, const PrimitiveList& primitives, DrawUtilCallback* callback = DE_NULL);
void	drawFromVAOBuffers		(const RenderContext& context, deUint32 program, int numVertexArrays, const VertexArrayBinding* vertexArrays, const PrimitiveList& primitives, DrawUtilCallback* callback = DE_NULL);

// Shorthands for PrimitiveList
namespace pr
{

#define DECLARE_PR_CTOR(NAME, TYPE)										\
inline PrimitiveList NAME (int numElements)								\
{																		\
	return PrimitiveList(TYPE, numElements);							\
}																		\
inline PrimitiveList NAME (int numElements, const deUint8* indices)		\
{																		\
	return PrimitiveList(TYPE, numElements, INDEXTYPE_UINT8, indices);	\
}																		\
inline PrimitiveList NAME (int numElements, const deUint16* indices)	\
{																		\
	return PrimitiveList(TYPE, numElements, INDEXTYPE_UINT16, indices);	\
}																		\
inline PrimitiveList NAME (int numElements, const deUint32* indices)	\
{																		\
	return PrimitiveList(TYPE, numElements, INDEXTYPE_UINT32, indices);	\
}																		\
struct DeclarePRCtor##NAME##Unused_s { int unused; }

DECLARE_PR_CTOR(Triangles,		PRIMITIVETYPE_TRIANGLES);
DECLARE_PR_CTOR(TriangleStrip,	PRIMITIVETYPE_TRIANGLE_STRIP);
DECLARE_PR_CTOR(TriangleFan,	PRIMITIVETYPE_TRIANGLE_FAN);

DECLARE_PR_CTOR(Lines,			PRIMITIVETYPE_LINES);
DECLARE_PR_CTOR(LineStrip,		PRIMITIVETYPE_LINE_STRIP);
DECLARE_PR_CTOR(LineLineLoop,	PRIMITIVETYPE_LINE_LOOP);

DECLARE_PR_CTOR(Points,			PRIMITIVETYPE_POINTS);

DECLARE_PR_CTOR(Patches,		PRIMITIVETYPE_PATCHES);

} // pr

// Shorthands for VertexArrayBinding
namespace va
{

#define DECLARE_VA_CTOR(NAME, DATATYPE, TYPE, CONVERT)																						\
inline VertexArrayBinding NAME (const std::string& name, int offset, int numComponents, int numElements, int stride, const DATATYPE* data)	\
{																																			\
	return VertexArrayBinding(BindingPoint(name, offset), VertexArrayPointer(TYPE, CONVERT, numComponents, numElements, stride, data));		\
}																																			\
inline VertexArrayBinding NAME (const std::string& name, int numComponents, int numElements, int stride, const DATATYPE* data)				\
{																																			\
	return NAME(name, 0, numComponents, numElements, stride, data);																			\
}																																			\
inline VertexArrayBinding NAME (int location, int numComponents, int numElements, int stride, const DATATYPE* data)							\
{																																			\
	return VertexArrayBinding(BindingPoint(location), VertexArrayPointer(TYPE, CONVERT, numComponents, numElements, stride, data));			\
}																																			\
struct DeclareVACtor##NAME##Unused_s { int unused; }

// Integer types
DECLARE_VA_CTOR(Uint8,			deUint8,		VTX_COMP_UNSIGNED_INT8,		VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Uint16,			deUint16,		VTX_COMP_UNSIGNED_INT16,	VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Uint32,			deUint32,		VTX_COMP_UNSIGNED_INT32,	VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Int8,			deInt8,			VTX_COMP_SIGNED_INT8,		VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Int16,			deInt16,		VTX_COMP_SIGNED_INT16,		VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Int32,			deInt32,		VTX_COMP_SIGNED_INT32,		VTX_COMP_CONVERT_NONE);

// Normalized integers.
DECLARE_VA_CTOR(Unorm8,			deUint8,		VTX_COMP_UNSIGNED_INT8,		VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);
DECLARE_VA_CTOR(Unorm16,		deUint16,		VTX_COMP_UNSIGNED_INT16,	VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);
DECLARE_VA_CTOR(Unorm32,		deUint32,		VTX_COMP_UNSIGNED_INT32,	VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);
DECLARE_VA_CTOR(Snorm8,			deInt8,			VTX_COMP_SIGNED_INT8,		VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);
DECLARE_VA_CTOR(Snorm16,		deInt16,		VTX_COMP_SIGNED_INT16,		VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);
DECLARE_VA_CTOR(Snorm32,		deInt32,		VTX_COMP_SIGNED_INT32,		VTX_COMP_CONVERT_NORMALIZE_TO_FLOAT);

// Integers converted to float.
DECLARE_VA_CTOR(Uint8Float,		deUint8,		VTX_COMP_UNSIGNED_INT8,		VTX_COMP_CONVERT_CAST_TO_FLOAT);
DECLARE_VA_CTOR(Uint16Float,	deUint16,		VTX_COMP_UNSIGNED_INT16,	VTX_COMP_CONVERT_CAST_TO_FLOAT);
DECLARE_VA_CTOR(Uint32Float,	deUint32,		VTX_COMP_UNSIGNED_INT32,	VTX_COMP_CONVERT_CAST_TO_FLOAT);
DECLARE_VA_CTOR(Int8Float,		deInt8,			VTX_COMP_SIGNED_INT8,		VTX_COMP_CONVERT_CAST_TO_FLOAT);
DECLARE_VA_CTOR(Int16Float,		deInt16,		VTX_COMP_SIGNED_INT16,		VTX_COMP_CONVERT_CAST_TO_FLOAT);
DECLARE_VA_CTOR(Int32Float,		deInt32,		VTX_COMP_SIGNED_INT32,		VTX_COMP_CONVERT_CAST_TO_FLOAT);

// Special types.
DECLARE_VA_CTOR(Fixed,			void,			VTX_COMP_FIXED,				VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Half,			void,			VTX_COMP_HALF_FLOAT,		VTX_COMP_CONVERT_NONE);
DECLARE_VA_CTOR(Float,			float,			VTX_COMP_FLOAT,				VTX_COMP_CONVERT_NONE);

#undef DECLARE_VA_CTOR

} // va

} // glu

#endif // _GLUDRAWUTIL_HPP