/*
	QGLEngineShaders
	Ivan Pelipenko peri4ko@yandex.ru

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef GLSHADERS_HEADERS_H
#define GLSHADERS_HEADERS_H

namespace QGLEngineShaders {

const int max_materials = 128;
const int max_lights    = 256 ;

const char qgl_common_head[] =
	"#version 400 core\n"
	"";

const char qgl_vertex_head[] =
	"layout(location = 1 ) in vec3 qgl_Vertex        ;\n"
	"layout(location = 2 ) in vec3 qgl_Normal        ;\n"
	"layout(location = 3 ) in vec3 qgl_Tangent       ;\n"
	"layout(location = 4 ) in vec3 qgl_Bitangent     ;\n"
	"layout(location = 5 ) in vec2 qgl_Texture       ;\n"
	"layout(location = 6 ) in uint qgl_Material      ;\n"
	"layout(location = 7 ) in uint qgl_ObjectSelected;\n"
	"layout(location = 8 ) in uint qgl_ObjectID      ;\n"
	"layout(location = 9 ) in vec4 qgl_ObjectColor   ;\n"
	"layout(location = 10) in mat4 qgl_ModelMatrix   ;\n"
	"out vec2 qgl_FragTexture;\n"
	"flat out uint qgl_MaterialIndex;\n"
	"uniform mat4 qgl_ViewMatrix;\n"
	"uniform mat4 qgl_ViewProjMatrix;\n"
	"mat3 qgl_getNormalMatrix()  {return inverse(mat3(qgl_ViewMatrix * qgl_ModelMatrix));}\n"
	"mat3 qgl_getTangentMatrix() {return mat3(qgl_ViewMatrix * qgl_ModelMatrix);}\n"
	"vec4 qgl_ftransform() {return qgl_ViewProjMatrix * (qgl_ModelMatrix * vec4(qgl_Vertex, 1));}\n"
	"";

const char qgl_fragment_head[] =
	"in vec2 qgl_FragTexture;\n"
	"flat in uint qgl_MaterialIndex;\n"
	"out vec4 qgl_FragData[gl_MaxDrawBuffers];\n"
	"vec4 qgl_materialTexture(uint type, vec2 coord, vec4 tex_shift) {\n"
	"	coord *= qgl_material[qgl_MaterialIndex].map[type].scale;\n"
	"	vec4 t = texture(qgl_texture_array[qgl_material[qgl_MaterialIndex].map[type].array_index],\n"
	"						   vec3(coord, qgl_material[qgl_MaterialIndex].map[type].map_index));\n"
	"	t += tex_shift;\n"
	"	t.rgb = t.rgb * qgl_material[qgl_MaterialIndex].map[type].amount + qgl_material[qgl_MaterialIndex].map[type].offset;\n"
	"	return t;\n"
	"}\n"
	"#define qgl_FragColor qgl_FragData[0]\n"
	"";

const char qgl_geometry_head[] =
	"";

const char qgl_structs[] =
	"#define QGL_MAPS_COUNT    6\n"
	"#define QGL_MAP_DIFFUSE   0\n"
	"#define QGL_MAP_NORMAL    1\n"
	"#define QGL_MAP_METALNESS 2\n"
	"#define QGL_MAP_ROUGHNESS 3\n"
	"#define QGL_MAP_EMISSION  4\n"
	"#define QGL_MAP_RELIEF    5\n"
	"#define QGL_TEXTURE_ARRAY_EMPTY 0\n"
	"#define QGL_TEXTURE_ARRAY_MAPS  1\n"
	"struct QGLMap {\n"
	"	float offset;\n"
	"	float amount;\n"
	"	vec2 scale;\n"
	"	uint array_index;\n"
	"	uint map_index;\n"
	"};\n"
	"struct QGLMaterial {\n"
	"	vec4 color_diffuse;\n"
	//"	vec4 color_specular;\n"
	"	vec4 color_emission;\n"
	"	float transparency;\n"
	"	float reflectivity;\n"
	"	float iof;\n"
	"	float dispersion;\n"
	"	QGLMap map[QGL_MAPS_COUNT];\n"
	"};\n"
	"struct QGLLightParameter {\n"
	"	vec4 color;\n"
	"	vec4 decay_intensity;\n"
	"	vec4 angles;\n"
	//"	sampler2DShadow shadow;\n"
	//"	sampler2D shadowColor\n"
	//"	mat4 shadowMatrix;\n"
	//"	vec4 shadowDir0;\n"
	//"	vec4 shadowDir1;\n"
	"};\n"
	"struct QGLLightPosition {\n"
	"	vec4 position;\n"
	"	vec4 direction;\n"
	"};\n"
	"";

const char qgl_uniform[] =
	"layout (std140) uniform QGLMaterialData {\n"
	"	QGLMaterial qgl_material[128];\n"
	"};\n"
	"layout (std140) uniform QGLLightParameterData {\n"
	"	QGLLightParameter qgl_light_parameter[256];\n"
	"};\n"
	"layout (std140) uniform QGLLightPositionData {\n"
	"	QGLLightPosition qgl_light_position[256];\n"
	"};\n"
	"uniform sampler2DArray qgl_texture_array[2];\n"
	"";

}

#endif // GLSHADERS_HEADERS_H