external/openglcts/modules/glesext/tessellation_shader/esextcTessellationShaderVertexOrdering.hpp

#ifndef _ESEXTCTESSELLATIONSHADERVERTEXORDERING_HPP
#define _ESEXTCTESSELLATIONSHADERVERTEXORDERING_HPP
/*-------------------------------------------------------------------------
 * OpenGL Conformance Test Suite
 * -----------------------------
 *
 * Copyright (c) 2014-2016 The Khronos Group Inc.
 *
 * 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
 */ /*-------------------------------------------------------------------*/

#include "../esextcTestCaseBase.hpp"
#include "esextcTessellationShaderUtils.hpp"
#include "gluShaderUtil.hpp"
#include "tcuDefs.hpp"

namespace glcts
{

/** Implementation of Test Case 26
 *
 *  Make sure that vertex ordering mode defined in a tessellation evaluation
 *  shader affects geometry generated by tessellation primitive generator and
 *  works as per extension specification (to the limit enforced by implementation-
 *  -dependent behaviour).
 *  Cover 'triangles' and 'quads' tessellation primitive generator modes.
 *  Make sure that points are unaffected by the vertex ordering mode.
 *  Make sure that by default counter-clockwise ordering is used.
 *  Note: This is based on 3.6.1 from ES spec 3.0.2 (p.102)
 *
 *  Technical details:
 *
 *  0. Consider the following set: {-1 (where valid), 1, MAX_TESS_GEN_LEVEL_EXT / 2,
 *     MAX_TESS_GEN_LEVEL_EXT}. All combinations of values from this set
 *     in regard to relevant inner/outer tessellation levels for all
 *     primitive generator modes should be checked by this test.
 *
 *  1. For cases where clock-wise ordering is expected, make sure that:
 *
 *     1/2 * sum(i=0..n-1)(x_i*y_(i@1) - x_(i@1)*y_i) < 0
 *
 *     where: n is number of vertices making up a single primitive,
 *            @ is an operator defined as x@y=(x+y)%n;
 *
 *     For cases where counterclock-wise ordering is expected, the value
 *     should be positive.
 *
 **/
class TessellationShaderVertexOrdering : public TestCaseBase
{
public:
	/* Public methods */
	TessellationShaderVertexOrdering(Context& context, const ExtParameters& extParams);

	virtual ~TessellationShaderVertexOrdering(void)
	{
	}

	virtual void		  deinit(void);
	void				  initTest(void);
	virtual IterateResult iterate(void);

private:
	/* Private type definitions */
	typedef struct _test_iteration
	{
		char*								 data;
		float								 inner_tess_levels[2];
		bool								 is_point_mode_enabled;
		unsigned int						 n_vertices;
		float								 outer_tess_levels[4];
		_tessellation_primitive_mode		 primitive_mode;
		_tessellation_shader_vertex_ordering vertex_ordering;

		_test_iteration()
		{
			memset(inner_tess_levels, 0, sizeof(inner_tess_levels));
			memset(outer_tess_levels, 0, sizeof(outer_tess_levels));

			data					= DE_NULL;
			is_point_mode_enabled	= false;
			n_vertices				= 0;
			primitive_mode			= TESSELLATION_SHADER_PRIMITIVE_MODE_UNKNOWN;
			vertex_ordering			= TESSELLATION_SHADER_VERTEX_ORDERING_UNKNOWN;
		}
	} _test_iteration;

	typedef std::vector<_test_iteration>	 _test_iterations;
	typedef _test_iterations::const_iterator _test_iterations_const_iterator;

	/* Private methods */
	void deinitTestIteration(_test_iteration& test_iteration);

	_test_iteration initTestIteration(const float* inner_tess_levels, const float* outer_tess_levels,
									  _tessellation_primitive_mode		   primitive_mode,
									  _tessellation_shader_vertex_ordering vertex_ordering, bool is_point_mode_enabled,
									  TessellationShaderUtils* utils);

	void verifyVertexOrderingCorrectness(const _test_iteration& test_iteration);

	void verifyVertexOrderingDoesNotChangeGeneratedPoints(const _test_iteration& test_iteration_a,
														  const _test_iteration& test_iteration_b);

	/* Private variables */
	glw::GLuint m_bo_id;
	glw::GLuint m_fs_id;
	glw::GLuint m_tc_id;
	glw::GLuint m_vs_id;
	glw::GLuint m_vao_id;

	_test_iterations		 m_tests;
	_test_iterations		 m_tests_points;
	TessellationShaderUtils* m_utils;
};

} // namespace glcts

#endif // _ESEXTCTESSELLATIONSHADERVERTEXORDERING_HPP