// draw objects with geometry shader defined by points
void draw_objects(const Shader& shad, const GLuint option) {
// number of objects (quads)
constexpr GLuint n {100};
shad.use();
GLuint vao{}, vbo{};
if (option == 0) {
gen_objects(vao, vbo, quad_vertices(), 5, 2);
const auto offset_arr = offsets_array(n);
const auto idx = shad.id();
for (GLuint i {0}; i < n; ++i) {
const GLint loc = glGetUniformLocation(idx,
std::string{"offsets_arr[" + std::to_string(i) + "]"}.
c_str());
glUniform2f(loc, offset_arr[i].x, offset_arr[i].y);
}
} else {
GLuint inst_vbo {gen_instance_buf(offsets_array(n))};
gen_objects_base(vao, vbo, quad_vertices(), 5, 2);
set_instance_data(inst_vbo);
}
glBindVertexArray(vao);
glDrawArraysInstanced(GL_TRIANGLES, 0, 6, n);
glBindVertexArray(0);
}
void Tree::Create(const std::vector<sf::Vector3f>& tile_vertices)
{
if(tile_vertices.size() != 4)
{
throw std::invalid_argument("tile_vertices must have 4 elements");
}
sf::Vector3f mid_point((tile_vertices[0].x + tile_vertices[2].x) / 2.0,
(tile_vertices[0].y + tile_vertices[2].y) / 2.0,
(tile_vertices[0].z + tile_vertices[2].z) / 2.0);
std::vector<sf::Vector3f> quad_vertices(4);
this->quads.resize(4);
quad_vertices[0] = tile_vertices[0];
quad_vertices[1] = mid_point;
quad_vertices[2] = mid_point + sf::Vector3f(0.0, 0.0, 1.0);
quad_vertices[3] = tile_vertices[0] + sf::Vector3f(0.0, 0.0, 1.0);
this->quads[0].create(quad_vertices);
quad_vertices[0] = tile_vertices[1];
quad_vertices[1] = mid_point;
quad_vertices[2] = mid_point + sf::Vector3f(0.0, 0.0, 1.0);
quad_vertices[3] = tile_vertices[1] + sf::Vector3f(0.0, 0.0, 1.0);
this->quads[1].create(quad_vertices);
quad_vertices[0] = tile_vertices[2];
quad_vertices[1] = mid_point;
quad_vertices[2] = mid_point + sf::Vector3f(0.0, 0.0, 1.0);
quad_vertices[3] = tile_vertices[2] + sf::Vector3f(0.0, 0.0, 1.0);
this->quads[2].create(quad_vertices);
quad_vertices[0] = tile_vertices[3];
quad_vertices[1] = mid_point;
quad_vertices[2] = mid_point + sf::Vector3f(0.0, 0.0, 1.0);
quad_vertices[3] = tile_vertices[3] + sf::Vector3f(0.0, 0.0, 1.0);
this->quads[3].create(quad_vertices);
this->type = rand() % 2;
}
