application/022_single_pass_edges/resources.cpp

Copyright Matus Chochlik. Distributed under the Boost Software License, Version 1.0. See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt

 
#include "resources.hpp"
 
#include <eagine/application/camera.hpp>
#include <eagine/application/context.hpp>
#include <eagine/embed.hpp>
#include <eagine/shapes/array.hpp>
#include <eagine/shapes/centered.hpp>
#include <eagine/shapes/icosahedron.hpp>
#include <eagine/shapes/scaled.hpp>
#include <oglplus/shapes/generator.hpp>
 
namespace eagine::application {
//------------------------------------------------------------------------------
// program
//------------------------------------------------------------------------------
void edges_program::init(execution_context& ec, video_context& vc) {
    const auto& glapi = vc.gl_api();
    const auto& gl = glapi;
 
    gl.create_program() >> prog;
 
    const auto prog_src{embed(EAGINE_ID(prog), "single_pass_edges.oglpprog")};
    gl.build_program(prog, prog_src.unpack(ec));
    gl.use_program(prog);
 
    gl.get_uniform_location(prog, "Projection") >> camera_loc;
    gl.get_uniform_location(prog, "ViewportDimensions") >> vp_dim_loc;
}
//------------------------------------------------------------------------------
void edges_program::clean_up(video_context& vc) {
    vc.gl_api().delete_program(std::move(prog));
}
//------------------------------------------------------------------------------
void edges_program::set_projection(video_context& vc, orbiting_camera& camera) {
    const auto [width, height] = vc.surface_size();
    const auto& glapi = vc.gl_api();
    glapi.set_uniform(prog, camera_loc, camera.matrix(vc));
    glapi.set_uniform(prog, vp_dim_loc, oglp::vec2(width, height));
}
//------------------------------------------------------------------------------
void edges_program::bind_position_location(
  video_context& vc,
  oglp::vertex_attrib_location loc) {
    vc.gl_api().bind_attrib_location(prog, loc, "Position");
}
//------------------------------------------------------------------------------
// geometry
//------------------------------------------------------------------------------
void icosahedron_geometry::init(execution_context& ec, video_context& vc) {
    const auto& glapi = vc.gl_api();
    const auto& gl = glapi;
 
    oglp::shape_generator shape(
      glapi,
      shapes::center(eagine::shapes::ortho_array_xyz(
        shapes::scale(
          shapes::unit_icosahedron(shapes::vertex_attrib_kind::position),
          {0.5F, 0.5F, 0.5F}),
        {1.F, 1.F, 1.F},
        {3, 3, 3})));
 
    ops.resize(std_size(shape.operation_count()));
    shape.instructions(glapi, cover(ops));
 
    // vao
    gl.gen_vertex_arrays() >> vao;
    gl.bind_vertex_array(vao);
 
    // positions
    gl.gen_buffers() >> positions;
    shape.attrib_setup(
      glapi,
      vao,
      positions,
      position_loc(),
      eagine::shapes::vertex_attrib_kind::position,
      ec.buffer());
 
    // indices
    gl.gen_buffers() >> indices;
    shape.index_setup(glapi, indices, ec.buffer());
}
//------------------------------------------------------------------------------
void icosahedron_geometry::clean_up(video_context& vc) {
    const auto& gl = vc.gl_api();
    gl.delete_buffers(std::move(indices));
    gl.delete_buffers(std::move(positions));
    gl.delete_vertex_arrays(std::move(vao));
}
//------------------------------------------------------------------------------
void icosahedron_geometry::draw(video_context& vc) {
    draw_using_instructions(vc.gl_api(), view(ops));
}
//------------------------------------------------------------------------------
} // namespace eagine::application