GfxModel.h

class DrawCall {
public:
	DrawCall(Model* model, Mesh* mesh, GLenum mode)
		: model_{model}, mesh_{mesh}, mode_{mode}
	void draw()
	{

		if (!model->indices.empty()) {
			glBindVertexArray(mesh->vao);
			if (mesh->acode == vertex_attrib::PositionNormalTexcoord) {
				glEnableVertexAttribArray(0);
				glEnableVertexAttribArray(1);
				glEnableVertexAttribArray(2);
			} else if (mesh->acode == vertex_attrib::PositionTangent) {
				glEnableVertexAttribArray(0);
				glEnableVertexAttribArray(1);
			} else {
				std::cerr << "Mesh not supported.\n";
				exit(1);				
			}

			// Setting up the materials.

			for (auto& part : model->parts) {
				glDrawElements(mode_, part.icount, GL_UNSIGNED_INT, part.istart);
			}

			if (mesh->acode == vertex_attrib::PositionNormalTexcoord) {
				glDisableVertexAttribArray(0);
				glDisableVertexAttribArray(1);
				glDisableVertexAttribArray(2);
			} else if (mesh->acode == vertex_attrib::PositionTangent) {
				glDisableVertexAttribArray(0);
				glDisableVertexAttribArray(1);
			} else {
				std::cerr << "Mesh not supported.\n";
				exit(1);				
			}

		}

		glBindVertexArray(mesh->vao);
		if (mesh->acode == vertex_attrib::PositionNormalTexcoord) {
			glEnableVertexAttribArray(0);
			glEnableVertexAttribArray(1);
			glEnableVertexAttribArray(2);
			glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_bufs[index]);

			if (mesh->primitive_restart_number != 0) {
				glEnable(GL_PRIMITIVE_RESTART);
				glPrimitiveRestartIndex(mesh->primitive_restart_number);
				glDrawElements(GL_LINE_STRIP, model->, GL_UNSIGNED_INT, (GLvoid*)0);
			}


		} else if (mesh->acode == vertex_attrib::PositionTangent) {
			glEnableVertexAttribArray(0);
			glEnableVertexAttribArray(1);
		} else {
			std::cerr << "Mesh not supported.\n";
			exit(1);
		}

		glEnable(GL_PRIMITIVE_RESTART);
		glPrimitiveRestartIndex(0xFFFFFFFF);
		glDrawElements(GL_LINE_STRIP, num_indices[index], GL_UNSIGNED_INT, (GLvoid*)0);

		for (auto attrib : attribs)
			glDisableVertexAttribArray(attrib);
		glBindVertexArray(0);
	}

private:
	Model* model_;
	Mesh* mesh_;
	GLenum mode_;
};


	void bind_vao_and_enable_attribs()
	{
		glBindVertexArray(mesh_->vao);
		if (acode == vertex_attrib::PositionNormalTexcoord) {
			glEnableVertexAttribArray(0);
			glEnableVertexAttribArray(1);
			glEnableVertexAttribArray(2);
		} else if (acode == vertex_attrib::PositionTangent) {
			glEnableVertexAttribArray(0);
			glEnableVertexAttribArray(1);
		} else {
			std::cerr << "Mesh not supported.\n";
			exit(1);				
		}

		if (primitive_restart_number) {
			glEnable(GL_PRIMITIVE_RESTART);
			glPrimitiveRestartIndex(primitive_restart_number);
		}
	}

	void unbind_vao_and_disable_attribs()
	{
		glBindVertexArray(mesh_->vao);
		if (acode == vertex_attrib::PositionNormalTexcoord) {
			glDisableVertexAttribArray(0);
			glDisableVertexAttribArray(1);
			glDisableVertexAttribArray(2);
		} else if (acode == vertex_attrib::PositionTangent) {
			glDisableVertexAttribArray(0);
			glDisableVertexAttribArray(1);
		} else {
			std::cerr << "Mesh not supported.\n";
			exit(1);				
		}

		if (primitive_restart_number) {
			glDisable(GL_PRIMITIVE_RESTART);
			glPrimitiveRestartIndex(primitive_restart_number);
		}
	}