示例#1
0
	CubeMapExample(void)
	 : shape_instr(make_shape.Instructions())
	 , shape_indices(make_shape.Indices())
	 , projection_matrix(prog, "ProjectionMatrix")
	 , camera_matrix(prog, "CameraMatrix")
	 , model_matrix(prog, "ModelMatrix")
	{
		// Set the vertex shader source
		vs.Source(
			"#version 330\n"
			"uniform mat4 ProjectionMatrix, CameraMatrix, ModelMatrix;"
			"in vec4 Position;"
			"in vec3 Normal;"
			"in vec2 TexCoord;"
			"out vec3 vertNormal;"
			"out vec3 vertLightDir;"
			"out vec3 vertLightRefl;"
			"out vec3 vertViewDir;"
			"out vec3 vertViewRefl;"
			"uniform vec3 LightPos;"
			"void main(void)"
			"{"
			"	gl_Position = ModelMatrix * Position;"
			"	vertNormal = mat3(ModelMatrix)*Normal;"
			"	vertLightDir = LightPos - gl_Position.xyz;"
			"	vertLightRefl = reflect("
			"		-normalize(vertLightDir),"
			"		normalize(vertNormal)"
			"	);"
			"	vertViewDir = ("
			"		vec4(0.0, 0.0, 1.0, 1.0)*"
			"		CameraMatrix"
			"	).xyz;"
			"	vertViewRefl = reflect("
			"		normalize(vertViewDir),"
			"		normalize(vertNormal)"
			"	);"
			"	gl_Position = ProjectionMatrix * CameraMatrix * gl_Position;"
			"}"
		);
		// compile it
		vs.Compile();

		// set the fragment shader source
		fs.Source(
			"#version 330\n"
			"uniform samplerCube TexUnit;"
			"in vec3 vertNormal;"
			"in vec3 vertLightDir;"
			"in vec3 vertLightRefl;"
			"in vec3 vertViewDir;"
			"in vec3 vertViewRefl;"
			"out vec4 fragColor;"
			"void main(void)"
			"{"
			"	float l = length(vertLightDir);"
			"	float d = dot("
			"		normalize(vertNormal), "
			"		normalize(vertLightDir)"
			"	) / l;"
			"	float s = dot("
			"		normalize(vertLightRefl),"
			"		normalize(vertViewDir)"
			"	);"
			"	vec3 lt = vec3(1.0, 1.0, 1.0);"
			"	vec3 env = texture(TexUnit, vertViewRefl).rgb;"
			"	fragColor = vec4("
			"		env * 0.4 + "
			"		(lt + env) * 1.5 * max(d, 0.0) + "
			"		lt * pow(max(s, 0.0), 64), "
			"		1.0"
			"	);"
			"}"
		);
		// compile it
		fs.Compile();

		// attach the shaders to the program
		prog.AttachShader(vs);
		prog.AttachShader(fs);
		// link and use it
		prog.Link();
		prog.Use();

		// bind the VAO for the shape
		shape.Bind();

		verts.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Positions(data);
			Buffer::Data(Buffer::Target::Array, data);
			VertexAttribArray attr(prog, "Position");
			attr.Setup(n_per_vertex, DataType::Float);
			attr.Enable();
		}

		normals.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Normals(data);
			Buffer::Data(Buffer::Target::Array, data);
			VertexAttribArray attr(prog, "Normal");
			attr.Setup(n_per_vertex, DataType::Float);
			attr.Enable();
		}

		// setup the texture
		{
			GLuint tex_side = 256;
			auto image = images::NewtonFractal(
				tex_side, tex_side,
				Vec3f(0.3f, 0.1f, 0.2f),
				Vec3f(1.0f, 0.8f, 0.9f),
				Vec2f(-1.0f, -1.0f),
				Vec2f( 1.0f,  1.0f),
				images::NewtonFractal::X4Minus1(),
				images::NewtonFractal::DefaultMixer()
			);
			auto bound_tex = Bind(tex, Texture::Target::CubeMap);
			bound_tex.MinFilter(TextureMinFilter::Linear);
			bound_tex.MagFilter(TextureMagFilter::Linear);
			bound_tex.WrapS(TextureWrap::ClampToEdge);
			bound_tex.WrapT(TextureWrap::ClampToEdge);
			bound_tex.WrapR(TextureWrap::ClampToEdge);

			for(int i=0; i!=6; ++i)
				Texture::Image2D(Texture::CubeMapFace(i), image);
		}
		// typechecked uniform with the exact sampler type
		// on compilers supporting strongly typed enums
		// you can use:
		//Typechecked<Uniform<SLtoCpp<SLDataType::SamplerCube>>>(prog, "TexUnit").Set(0);
		// without strongly typed enums you need to do:
		typedef SLtoCpp<OGLPLUS_CONST_ENUM_VALUE(SLDataType::SamplerCube)> GLSLsamplerCube;
		Typechecked<Uniform<GLSLsamplerCube>>(prog, "TexUnit").Set(0);

		//
		Uniform<Vec3f>(prog, "LightPos").Set(Vec3f(3.0f, 5.0f, 4.0f));
		//
		gl.ClearColor(0.2f, 0.05f, 0.1f, 0.0f);
		gl.ClearDepth(1.0f);
		gl.Enable(Capability::DepthTest);

		gl.Enable(Capability::CullFace);
		gl.FrontFace(make_shape.FaceWinding());
		gl.CullFace(Face::Back);
	}
示例#2
0
	HaloExample(void)
	 : make_shape()
	 , shape_indices(make_shape.Indices())
	 , shape_instr(make_shape.Instructions())
	 , vs_shape(ObjectDesc("Shape VS"))
	 , vs_plane(ObjectDesc("Plane VS"))
	 , fs_shape(ObjectDesc("Shape FS"))
	 , fs_plane(ObjectDesc("Plane FS"))
	 , vs_halo(ObjectDesc("Halo VS"))
	 , gs_halo(ObjectDesc("Halo GS"))
	 , fs_halo(ObjectDesc("Halo FS"))
	 , shape_projection_matrix(shape_prog, "ProjectionMatrix")
	 , shape_camera_matrix(shape_prog, "CameraMatrix")
	 , shape_model_matrix(shape_prog, "ModelMatrix")
	 , plane_projection_matrix(plane_prog, "ProjectionMatrix")
	 , plane_camera_matrix(plane_prog, "CameraMatrix")
	 , halo_projection_matrix(halo_prog, "ProjectionMatrix")
	 , halo_camera_matrix(halo_prog, "CameraMatrix")
	 , halo_model_matrix(halo_prog, "ModelMatrix")
	{
		vs_shape.Source(
			"#version 140\n"
			"in vec4 Position;"
			"in vec3 Normal;"
			"uniform mat4 ProjectionMatrix, CameraMatrix, ModelMatrix;"
			"uniform vec3 LightPos;"
			"out vec3 vertNormal;"
			"out vec3 vertViewNormal;"
			"out vec3 vertLight;"
			"void main(void)"
			"{"
			"	gl_Position = ModelMatrix * Position;"
			"	vertNormal = mat3(ModelMatrix)*Normal;"
			"	vertViewNormal = mat3(CameraMatrix)*vertNormal;"
			"	vertLight = LightPos - gl_Position.xyz;"
			"	gl_Position = ProjectionMatrix * CameraMatrix * gl_Position;"
			"}"
		);
		vs_shape.Compile();

		fs_shape.Source(
			"#version 140\n"
			"in vec3 vertNormal;"
			"in vec3 vertViewNormal;"
			"in vec3 vertLight;"
			"uniform mat4 CameraMatrix;"
			"out vec4 fragColor;"
			"void main(void)"
			"{"
			"	float ltlen = sqrt(length(vertLight));"
			"	float ltexp = dot("
			"		normalize(vertNormal),"
			"		normalize(vertLight)"
			"	);"
			"	float lview = dot("
			"		normalize(vertLight),"
			"		normalize(vec3("
			"			CameraMatrix[0][2],"
			"			CameraMatrix[1][2],"
			"			CameraMatrix[2][2] "
			"		))"
			"	);"
			"	float depth = normalize(vertViewNormal).z;"
			"	vec3 ftrefl = vec3(0.9, 0.8, 0.7);"
			"	vec3 scatter = vec3(0.9, 0.6, 0.1);"
			"	vec3 bklt = vec3(0.8, 0.6, 0.4);"
			"	vec3 ambient = vec3(0.5, 0.4, 0.3);"
			"	fragColor = vec4("
			"		pow(max(ltexp, 0.0), 8.0)*ftrefl+"
			"		( ltexp+1.0)/ltlen*pow(depth,2.0)*scatter+"
			"		(-ltexp+1.0)/ltlen*(1.0-depth)*scatter+"
			"		(-lview+1.0)*0.6*(1.0-abs(depth))*bklt+"
			"		0.2*ambient,"
			"		1.0"
			"	);"
			"}"
		);
		fs_shape.Compile();

		shape_prog.AttachShader(vs_shape);
		shape_prog.AttachShader(fs_shape);
		shape_prog.Link();

		vs_plane.Source(
			"#version 140\n"
			"in vec4 Position;"
			"in vec3 Normal;"
			"uniform mat4 ProjectionMatrix, CameraMatrix;"
			"uniform vec3 LightPos;"
			"out vec3 vertNormal;"
			"out vec3 vertLight;"
			"void main(void)"
			"{"
			"	gl_Position = "
			"		ProjectionMatrix *"
			"		CameraMatrix *"
			"		Position;"
			"	vertNormal = Normal;"
			"	vertLight = LightPos-Position.xyz;"
			"}"
		);
		vs_plane.Compile();

		fs_plane.Source(
			"#version 140\n"
			"in vec3 vertNormal;"
			"in vec3 vertLight;"
			"out vec4 fragColor;"
			"void main(void)"
			"{"
			"	float l = sqrt(length(vertLight));"
			"	float e = dot("
			"		vertNormal,"
			"		normalize(vertLight)"
			"	);"
			"	float d = l > 0.0 ? e / l : 0.0;"
			"	float i = 0.2 + 2.5 * d;"
			"	fragColor = vec4(0.8*i, 0.7*i, 0.4*i, 1.0);"
			"}"
		);
		fs_plane.Compile();

		plane_prog.AttachShader(vs_plane);
		plane_prog.AttachShader(fs_plane);
		plane_prog.Link();

		vs_halo.Source(
			"#version 150\n"
			"in vec4 Position;"
			"in vec3 Normal;"
			"uniform mat4 ModelMatrix, CameraMatrix;"
			"out vec3 vertNormal;"
			"out float vd;"
			"void main(void)"
			"{"
			"	gl_Position = "
			"		CameraMatrix *"
			"		ModelMatrix *"
			"		Position;"
			"	vertNormal = ("
			"		CameraMatrix *"
			"		ModelMatrix *"
			"		vec4(Normal, 0.0)"
			"	).xyz;"
			"	vd = vertNormal.z;"
			"}"
		);
		vs_halo.Compile();

		gs_halo.Source(
			"#version 150\n"
			"layout(triangles) in;"
			"layout(triangle_strip, max_vertices = 12) out;"

			"in vec3 vertNormal[];"
			"in float vd[];"

			"uniform mat4 CameraMatrix, ProjectionMatrix;"
			"uniform vec3 LightPos;"

			"out float geomAlpha;"

			"void main(void)"
			"{"
			"	for(int v=0; v!=3; ++v)"
			"	{"
			"		int a = v, b = (v+1)%3, c = (v+2)%3;"
			"		vec4 pa = gl_in[a].gl_Position;"
			"		vec4 pb = gl_in[b].gl_Position;"
			"		vec4 pc = gl_in[c].gl_Position;"
			"		vec4 px, py;"
			"		vec3 na = vertNormal[a];"
			"		vec3 nb = vertNormal[b];"
			"		vec3 nc = vertNormal[c];"
			"		vec3 nx, ny;"
			"		if(vd[a] == 0.0 && vd[b] == 0.0)"
			"		{"
			"			px = pa;"
			"			nx = na;"
			"			py = pb;"
			"			ny = nb;"
			"		}"
			"		else if(vd[a] > 0.0 && vd[b] < 0.0)"
			"		{"
			"			float x = vd[a]/(vd[a]-vd[b]);"
			"			float y;"
			"			px = mix(pa, pb, x);"
			"			nx = mix(na, nb, x);"
			"			if(vd[c] < 0.0)"
			"			{"
			"				y = vd[a]/(vd[a]-vd[c]);"
			"				py = mix(pa, pc, y);"
			"				ny = mix(na, nc, y);"
			"			}"
			"			else"
			"			{"
			"				y = vd[c]/(vd[c]-vd[b]);"
			"				py = mix(pc, pb, y);"
			"				ny = mix(nc, nb, y);"
			"			}"
			"		}"
			"		else continue;"
			"		vec4 gx1 = vec4(px.xyz, 1.0);"
			"		vec4 gy1 = vec4(py.xyz, 1.0);"
			"		vec4 gx2 = vec4(px.xyz + nx*0.3, 1.0);"
			"		vec4 gy2 = vec4(py.xyz + ny*0.3, 1.0);"
			"		gl_Position = ProjectionMatrix * gy1;"
			"		geomAlpha = 1.0;"
			"		EmitVertex();"
			"		gl_Position = ProjectionMatrix * gx1;"
			"		geomAlpha = 1.0;"
			"		EmitVertex();"
			"		gl_Position = ProjectionMatrix * gy2;"
			"		geomAlpha = 0.0;"
			"		EmitVertex();"
			"		gl_Position = ProjectionMatrix * gx2;"
			"		geomAlpha = 0.0;"
			"		EmitVertex();"
			"		EndPrimitive();"
			"		break;"
			"	}"
			"}"
		);
		gs_halo.Compile();

		fs_halo.Source(
			"#version 150\n"
			"in float geomAlpha;"
			"out vec4 fragColor;"
			"void main(void)"
			"{"
			"	fragColor = vec4("
			"		0.5, 0.4, 0.3,"
			"		pow(geomAlpha, 2.0)"
			"	);"
			"}"
		);
		fs_halo.Compile();

		halo_prog.AttachShader(vs_halo);
		halo_prog.AttachShader(gs_halo);
		halo_prog.AttachShader(fs_halo);
		halo_prog.Link();

		// bind the VAO for the shape
		shape.Bind();

		// bind the VBO for the shape vertices
		shape_verts.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Positions(data);
			Buffer::Data(Buffer::Target::Array, data);

			VertexAttribSlot location;
			if(VertexArrayAttrib::QueryCommonLocation(
				MakeGroup(shape_prog, halo_prog),
				"Position",
				location
			))
			{
				VertexArrayAttrib attr(location);
				attr.Setup<GLfloat>(n_per_vertex);
				attr.Enable();
			}
			else OGLPLUS_ABORT("Inconsistent 'Position' location");
		}

		// bind the VBO for the shape normals
		shape_normals.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Normals(data);
			Buffer::Data(Buffer::Target::Array, data);

			shape_prog.Use();
			VertexArrayAttrib attr(shape_prog, "Normal");
			attr.Setup<GLfloat>(n_per_vertex);
			attr.Enable();
		}

		// bind the VAO for the plane
		plane.Bind();

		// bind the VBO for the plane vertices
		plane_verts.Bind(Buffer::Target::Array);
		{
			GLfloat data[4*3] = {
				-9.0f, 0.0f,  9.0f,
				-9.0f, 0.0f, -9.0f,
				 9.0f, 0.0f,  9.0f,
				 9.0f, 0.0f, -9.0f
			};
			Buffer::Data(Buffer::Target::Array, 4*3, data);
			plane_prog.Use();
			VertexArrayAttrib attr(plane_prog, "Position");
			attr.Setup<Vec3f>();
			attr.Enable();
		}

		// bind the VBO for the plane normals
		plane_normals.Bind(Buffer::Target::Array);
		{
			GLfloat data[4*3] = {
				-0.1f, 1.0f,  0.1f,
				-0.1f, 1.0f, -0.1f,
				 0.1f, 1.0f,  0.1f,
				 0.1f, 1.0f, -0.1f
			};
			Buffer::Data(Buffer::Target::Array, 4*3, data);
			plane_prog.Use();
			VertexArrayAttrib attr(plane_prog, "Normal");
			attr.Setup<Vec3f>();
			attr.Enable();
		}

		Vec3f lightPos(2.0f, 2.5f, 9.0f);

		ProgramUniform<Vec3f>(shape_prog, "LightPos").Set(lightPos);
		ProgramUniform<Vec3f>(plane_prog, "LightPos").Set(lightPos);

		gl.ClearColor(0.2f, 0.2f, 0.2f, 0.0f);
		gl.ClearDepth(1.0f);
		gl.ClearStencil(0);

		gl.Enable(Capability::DepthTest);
		gl.BlendFunc(BlendFn::SrcAlpha, BlendFn::One);
	}
示例#3
0
	ShadowVolExample(const ExampleParams& params)
	 : shape_instr(make_shape.Instructions())
	 , shape_indices(make_shape.Indices())
	 , shape_vs(ShaderType::Vertex, ObjectDesc("Shape vertex"))
	 , depth_vs(ShaderType::Vertex, ObjectDesc("Depth vertex"))
	 , light_vs(ShaderType::Vertex, ObjectDesc("Light vertex"))
	 , depth_gs(ShaderType::Geometry, ObjectDesc("Depth geometry"))
	 , light_gs(ShaderType::Geometry, ObjectDesc("Light geometry"))
	 , shape_fs(ShaderType::Fragment, ObjectDesc("Shape fragment"))
	 , depth_fs(ShaderType::Fragment, ObjectDesc("Depthfragment"))
	 , light_fs(ShaderType::Fragment, ObjectDesc("Light fragment"))
	 , shape_prog(ObjectDesc("Shape"))
	 , depth_prog(ObjectDesc("Depth"))
	 , light_prog(ObjectDesc("Light"))
	 , tex_side(128)
	 , sample_count(params.HighQuality()?1024:128)
	{
		shape_vs.Source(
			"#version 330\n"
			"uniform mat4 ProjectionMatrix, CameraMatrix, ModelMatrix;"
			"in vec4 Position;"
			"in vec3 Normal;"
			"in vec2 TexCoord;"
			"out vec3 vertNormal;"
			"out vec3 vertLightDir;"
			"out vec3 vertLightRefl;"
			"out vec3 vertViewDir;"
			"out vec3 vertViewRefl;"
			"uniform vec3 LightPos;"
			"void main(void)"
			"{"
			"	gl_Position = ModelMatrix * Position;"
			"	vertNormal = mat3(ModelMatrix)*Normal;"
			"	vertLightDir = LightPos - gl_Position.xyz;"
			"	vertLightRefl = reflect("
			"		-normalize(vertLightDir),"
			"		normalize(vertNormal)"
			"	);"
			"	vertViewDir = (vec4(0.0, 0.0, 1.0, 1.0)* CameraMatrix).xyz;"
			"	vertViewRefl = reflect("
			"		normalize(vertViewDir),"
			"		normalize(vertNormal)"
			"	);"
			"	gl_Position = ProjectionMatrix * CameraMatrix * gl_Position;"
			"}"
		);
		shape_vs.Compile();

		shape_fs.Source(
			"#version 330\n"
			"in vec3 vertNormal;"
			"in vec3 vertLightDir;"
			"in vec3 vertLightRefl;"
			"in vec3 vertViewDir;"
			"in vec3 vertViewRefl;"
			"out vec4 fragColor;"
			"void main(void)"
			"{"
			"	float l = length(vertLightDir);"
			"	float d = dot("
			"		normalize(vertNormal), "
			"		normalize(vertLightDir)"
			"	) / l;"
			"	float s = dot("
			"		normalize(vertLightRefl),"
			"		normalize(vertViewDir)"
			"	);"
			"	vec3 ambi = vec3(0.6, 0.3, 0.5);"
			"	vec3 diff = vec3(0.9, 0.7, 0.8);"
			"	vec3 spec = vec3(1.0, 0.9, 0.95);"
			"	fragColor = vec4("
			"		ambi * 0.3 + "
			"		diff * 0.7 * max(d, 0.0) + "
			"		spec * pow(max(s, 0.0), 64), "
			"		1.0"
			"	);"
			"}"
		);
		shape_fs.Compile();

		shape_prog.AttachShader(shape_vs);
		shape_prog.AttachShader(shape_fs);
		shape_prog.Link();

		depth_vs.Source(
			"#version 330\n"
			"uniform mat4 ModelMatrix;"
			"uniform vec3 LightPos;"
			"in vec4 Position;"
			"void main(void)"
			"{"
			"	gl_Position = "
			"		mat4("
			"			1.0, 0.0, 0.0, -LightPos.x,"
			"			0.0, 1.0, 0.0, -LightPos.y,"
			"			0.0, 0.0, 1.0, -LightPos.z,"
			"			0.0, 0.0, 0.0,  1.0"
			"		)*"
			"		ModelMatrix *"
			"		mat4("
			"			10.0,  0.0,  0.0,  0.0,"
			"			 0.0, 10.0,  0.0,  0.0,"
			"			 0.0,  0.0, 10.0,  0.0,"
			"			 0.0,  0.0,  0.0,  1.0 "
			"		)*"
			"		Position;"
			"}"
		);
		depth_vs.Compile();

		depth_gs.Source(
			"#version 330\n"
			"layout(triangles) in;"
			"layout(triangle_strip, max_vertices = 18) out;"

			"uniform mat4 ProjectionMatrix;"

			"const mat4 CubeFaceMatrix[6] = mat4[6]("
			"	mat4("
			"		 0.0,  0.0, -1.0,  0.0,"
			"		 0.0, -1.0,  0.0,  0.0,"
			"		-1.0,  0.0,  0.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	), mat4("
			"		 0.0,  0.0,  1.0,  0.0,"
			"		 0.0, -1.0,  0.0,  0.0,"
			"		 1.0,  0.0,  0.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	), mat4("
			"		 1.0,  0.0,  0.0,  0.0,"
			"		 0.0,  0.0, -1.0,  0.0,"
			"		 0.0,  1.0,  0.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	), mat4("
			"		 1.0,  0.0,  0.0,  0.0,"
			"		 0.0,  0.0,  1.0,  0.0,"
			"		 0.0, -1.0,  0.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	), mat4("
			"		 1.0,  0.0,  0.0,  0.0,"
			"		 0.0, -1.0,  0.0,  0.0,"
			"		 0.0,  0.0, -1.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	), mat4("
			"		-1.0,  0.0,  0.0,  0.0,"
			"		 0.0, -1.0,  0.0,  0.0,"
			"		 0.0,  0.0,  1.0,  0.0,"
			"		 0.0,  0.0,  0.0,  1.0 "
			"	)"
			");"

			"void main(void)"
			"{"
			"	for(gl_Layer=0; gl_Layer!=6; ++gl_Layer)"
			"	{"
			"		for(int i=0; i!=3; ++i)"
			"		{"
			"			gl_Position = "
			"				ProjectionMatrix *"
			"				CubeFaceMatrix[gl_Layer]*"
			"				gl_in[i].gl_Position;"
			"			EmitVertex();"
			"		}"
			"		EndPrimitive();"
			"	}"
			"}"
		);
		depth_gs.Compile();

		depth_fs.Source(
			"#version 330\n"
			"void main(void)"
			"{"
			"	gl_FragDepth = gl_FragCoord.z;"
			"}"
		);
		depth_fs.Compile();

		depth_prog.AttachShader(depth_vs);
		depth_prog.AttachShader(depth_gs);
		depth_prog.AttachShader(depth_fs);
		depth_prog.Link();
		depth_prog.Use();

		Uniform<Mat4f>(depth_prog, "ProjectionMatrix").Set(
			CamMatrixf::PerspectiveX(
				RightAngles(1.0),
				1.0,
				0.1,
				10.0
			)
		);

		// bind the VAO for the shape
		shape.Bind();

		shape_positions.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Positions(data);
			Buffer::Data(Buffer::Target::Array, data);

			VertexAttribSlot location;
			if(VertexAttribArray::QueryCommonLocation(
				"Position",
				location,
				shape_prog,
				depth_prog
			))
			{
				VertexAttribArray shape_attr(location);
				shape_attr.Setup(n_per_vertex, DataType::Float);
				shape_attr.Enable();
			}
			else assert(!"Inconsistent 'Position' location");
		}

		shape_normals.Bind(Buffer::Target::Array);
		{
			std::vector<GLfloat> data;
			GLuint n_per_vertex = make_shape.Normals(data);
			Buffer::Data(Buffer::Target::Array, data);

			shape_prog.Use();
			VertexAttribArray attr(shape_prog, "Normal");
			attr.Setup(n_per_vertex, DataType::Float);
			attr.Enable();
		}

		light_vs.Source(
			"#version 330\n"
			"in vec3 Position;"
			"out float vertZOffs;"
			"uniform vec3 LightPos;"
			"uniform int SampleCount;"
			"void main(void)"
			"{"
			"	float hp = (SampleCount-1) * 0.5;"
			"	vertZOffs = (gl_InstanceID - hp)/hp;"
			"	gl_Position = vec4(Position + LightPos, 1.0);"
			"}"
		);
		light_vs.Compile();

		light_gs.Source(
			"#version 330\n"
			"layout(points) in;"
			"layout(triangle_strip, max_vertices = 4) out;"
			"in float vertZOffs[];"
			"out vec4 geomPosition;"
			"uniform mat4 CameraMatrix, ProjectionMatrix;"
			"uniform vec3 ViewX, ViewY, ViewZ;"
			"uniform float LightVolSize;"
			"void main(void)"
			"{"
			"	float zo = vertZOffs[0];"
			"	float yo[2] = float[2](-1.0, 1.0);"
			"	float xo[2] = float[2](-1.0, 1.0);"
			"	for(int j=0;j!=2;++j)"
			"	for(int i=0;i!=2;++i)"
			"	{"
			"		geomPosition = vec4("
			"			gl_in[0].gl_Position.xyz+"
			"			ViewX * xo[i] * LightVolSize+"
			"			ViewY * yo[j] * LightVolSize+"
			"			ViewZ * zo    * LightVolSize,"
			"			1.0"
			"		);"
			"		gl_Position = "
			"			ProjectionMatrix *"
			"			CameraMatrix *"
			"			geomPosition;"
			"		EmitVertex();"
			"	}"
			"	EndPrimitive();"
			"}"
		);
		light_gs.Compile();

		light_fs.Source(
			"#version 330\n"
			"in vec4 geomPosition;"
			"out vec4 fragColor;"
			"uniform samplerCubeShadow ShadowMap;"
			"uniform int SampleCount;"
			"uniform vec3 LightPos;"
			"void main(void)"
			"{"
			"	vec3 LightDir = geomPosition.xyz - LightPos;"
			"	vec4 ShadowCoord = vec4("
			"		normalize(LightDir),"
			"		length(LightDir)"
			"	);"
			"	float s = texture(ShadowMap, ShadowCoord);"
			"	float alpha = s / (SampleCount * pow(length(LightDir), 2));"
			"	fragColor = vec4(1.0, 1.0, 1.0, alpha);"
			"}"
		);
		light_fs.Compile();

		light_prog.AttachShader(light_vs);
		light_prog.AttachShader(light_gs);
		light_prog.AttachShader(light_fs);
		light_prog.Link();
		light_prog.Use();

		// bind the VAO for the light volume
		light.Bind();

		// bind the VBO for the light volume plane positions
		light_positions.Bind(Buffer::Target::Array);
		{
			GLfloat position[3] = {0.0, 0.0, 0.0};
			Buffer::Data(Buffer::Target::Array, 3, position);
			VertexAttribArray attr(light_prog, "Position");
			attr.Setup(3, DataType::Float);
			attr.Enable();
		}

		Uniform<GLint>(light_prog, "SampleCount").Set(sample_count);
		Uniform<GLfloat>(light_prog, "LightVolSize").Set(4);
		UniformSampler(light_prog, "ShadowMap").Set(0);

		// Setup the texture and the offscreen FBO
		Texture::Active(0);
		{
			auto bound_tex = Bind(depth_tex, Texture::Target::CubeMap);
			bound_tex.MinFilter(TextureMinFilter::Linear);
			bound_tex.MagFilter(TextureMagFilter::Linear);
			bound_tex.WrapS(TextureWrap::ClampToEdge);
			bound_tex.WrapT(TextureWrap::ClampToEdge);
			bound_tex.WrapR(TextureWrap::ClampToEdge);
			bound_tex.CompareFunc(CompareFunction::LEqual);
			bound_tex.CompareMode(
				TextureCompareMode::CompareRefToTexture
			);

			for(int i=0; i!=6; ++i)
			{
				Texture::Image2D(
					Texture::CubeMapFace(i),
					0,
					PixelDataInternalFormat::DepthComponent,
					tex_side, tex_side,
					0,
					PixelDataFormat::DepthComponent,
					PixelDataType::Float,
					nullptr
				);
			}

			auto bound_fbo = Bind(
				depth_fbo,
				Framebuffer::Target::Draw
			);
			bound_fbo.AttachTexture(
				FramebufferAttachment::Depth,
				depth_tex,
				0
			);
		}
		//
		gl.ClearColor(0.2f, 0.05f, 0.1f, 0.0f);
		gl.ClearDepth(1.0f);
		gl.Enable(Capability::DepthTest);

		gl.Enable(Capability::CullFace);
		gl.FrontFace(make_shape.FaceWinding());
		gl.CullFace(Face::Back);

		gl.BlendFunc(BlendFunction::SrcAlpha, BlendFunction::One);
	}