KlassischeKeplerKriege/game/renderer.cpp

#include "renderer.hpp"

static const char *vss =
#include "main.vs"
    ;
static const char *fss =
#include "main.fs"
    ;

#include <vector>
#include "glm/glm.hpp"
#include "glm/vec2.hpp"
#include "glm/vec3.hpp"
#include "glm/gtc/type_ptr.hpp"

endofthejedi::Renderer::Renderer() {
    m_shader.load(vss, GL_VERTEX_SHADER);
    m_shader.load(fss, GL_FRAGMENT_SHADER);
}

endofthejedi::Renderer::~Renderer() {}

void endofthejedi::Renderer::render(const game::State *state) {
    m_shader.bind();

    std::vector<glm::vec3> positions;
    std::vector<glm::vec4> colors;
    std::vector<GLfloat> radii;
    std::vector<GLfloat> reflections;

    for (const game::Planet *planet : state->planets) {
        positions.push_back(glm::vec3(planet->position, -10.0f));
        radii.push_back(planet->radius);
        colors.push_back(glm::vec4(1.0f, 0.0f, 0.0f, 0.5f));
    }

    glUniform1f(m_shader.location("aspectratio"), 16.0f/9.0f);
    glUniform1i(m_shader.location("reflections"), 1);
    glUniform3f(m_shader.location("l_position"), 0.6f, 0.1f, 0.0f);
    glUniform1f(m_shader.location("l_radius"), 1.0f);
    glUniform3fv(m_shader.location("s_positions"), positions.size(),
                 glm::value_ptr(positions[0]));
    glUniform4fv(m_shader.location("s_colors"), colors.size(),
                 glm::value_ptr(colors[0]));
    glUniform1fv(m_shader.location("s_radii"), radii.size(), &radii[0]);
    glUniform1i(m_shader.location("s_length"), positions.size());

    // render fullscreen quad with legacy opengl (too lazy, sorry)
    glBegin(GL_QUADS);
    glVertex2f(-1.0f, -1.0f);
    glVertex2f(1.0f, -1.0f);
    glVertex2f(1.0f, 1.0f);
    glVertex2f(-1.0f, 1.0f);
    glEnd();
}

void endofthejedi::Renderer::drawCircle(float x, float y, float radius, float r,
                                        float g, float b, int numSides) {
    glBegin(GL_TRIANGLE_FAN);
    glVertex2f(x, y); // center of circle
    for (int i = 0; i <= numSides; i++) {
        glColor3f(r, g, b);
        glVertex2f(x + (radius * cos(i * 2 * M_PI / numSides)),
                   y + (radius * sin(i * 2 * M_PI / numSides)));
    }
    glEnd();
}