SFMLDebugDraw.cpp

// Debug draw for Box2D 2.2.1 - 2.3.0 for SFML 2.0 - SFMLDebugDraw.cpp
// Copyright (C) 2013  Matija Lovrekovic
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#include "SFMLDebugDraw.h"

SFMLDebugDraw::SFMLDebugDraw(sf::RenderWindow &window) : m_window(&window) {}

void SFMLDebugDraw::DrawPolygon(const b2Vec2 *vertices, int32 vertexCount,
                                const b2Color &color) {
  sf::ConvexShape polygon(vertexCount);
  sf::Vector2f center;
  for (int i = 0; i < vertexCount; i++) {
    // polygon.setPoint(i, SFMLDraw::B2VecToSFVec(vertices[i]));
    sf::Vector2f transformedVec = SFMLDebugDraw::B2VecToSFVec(vertices[i]);
    polygon.setPoint(
        i, sf::Vector2f(std::floor(transformedVec.x),
                        std::floor(transformedVec.y))); // flooring the coords
                                                        // to fix distorted
                                                        // lines on flat
                                                        // surfaces
  } // they still show up though.. but less frequently
  polygon.setOutlineThickness(-1.f);
  polygon.setFillColor(sf::Color::Transparent);
  polygon.setOutlineColor(SFMLDebugDraw::GLColorToSFML(color));

  m_window->draw(polygon);
}
void SFMLDebugDraw::DrawSolidPolygon(const b2Vec2 *vertices, int32 vertexCount,
                                     const b2Color &color) {
  sf::ConvexShape polygon(vertexCount);
  for (int i = 0; i < vertexCount; i++) {
    // polygon.setPoint(i, SFMLDraw::B2VecToSFVec(vertices[i]));
    sf::Vector2f transformedVec = SFMLDebugDraw::B2VecToSFVec(vertices[i]);
    polygon.setPoint(
        i, sf::Vector2f(std::floor(transformedVec.x),
                        std::floor(transformedVec.y))); // flooring the coords
                                                        // to fix distorted
                                                        // lines on flat
                                                        // surfaces
  } // they still show up though.. but less frequently
  polygon.setOutlineThickness(-1.f);
  polygon.setFillColor(SFMLDebugDraw::GLColorToSFML(color, 60));
  polygon.setOutlineColor(SFMLDebugDraw::GLColorToSFML(color));

  m_window->draw(polygon);
}
void SFMLDebugDraw::DrawCircle(const b2Vec2 &center, float32 radius,
                               const b2Color &color) {
  sf::CircleShape circle(radius * sfdd::SCALE);
  circle.setOrigin(radius * sfdd::SCALE, radius * sfdd::SCALE);
  circle.setPosition(SFMLDebugDraw::B2VecToSFVec(center));
  circle.setFillColor(sf::Color::Transparent);
  circle.setOutlineThickness(-1.f);
  circle.setOutlineColor(SFMLDebugDraw::GLColorToSFML(color));

  m_window->draw(circle);
}
void SFMLDebugDraw::DrawSolidCircle(const b2Vec2 &center, float32 radius,
                                    const b2Vec2 &axis, const b2Color &color) {
  sf::CircleShape circle(radius * sfdd::SCALE);
  circle.setOrigin(radius * sfdd::SCALE, radius * sfdd::SCALE);
  circle.setPosition(SFMLDebugDraw::B2VecToSFVec(center));
  circle.setFillColor(SFMLDebugDraw::GLColorToSFML(color, 60));
  circle.setOutlineThickness(1.f);
  circle.setOutlineColor(SFMLDebugDraw::GLColorToSFML(color));

  b2Vec2 endPoint = center + radius * axis;
  sf::Vertex line[2] = {
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(center),
                 SFMLDebugDraw::GLColorToSFML(color)),
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(endPoint),
                 SFMLDebugDraw::GLColorToSFML(color)),
  };

  m_window->draw(circle);
  m_window->draw(line, 2, sf::Lines);
}
void SFMLDebugDraw::DrawSegment(const b2Vec2 &p1, const b2Vec2 &p2,
                                const b2Color &color) {
  sf::Vertex line[] = {sf::Vertex(SFMLDebugDraw::B2VecToSFVec(p1),
                                  SFMLDebugDraw::GLColorToSFML(color)),
                       sf::Vertex(SFMLDebugDraw::B2VecToSFVec(p2),
                                  SFMLDebugDraw::GLColorToSFML(color))};

  m_window->draw(line, 2, sf::Lines);
}
void SFMLDebugDraw::DrawTransform(const b2Transform &xf) {
  float lineLength = 0.4;

  /*b2Vec2 xAxis(b2Vec2(xf.p.x + (lineLength * xf.q.c), xf.p.y + (lineLength *
   * xf.q.s)));*/
  b2Vec2 xAxis = xf.p + lineLength * xf.q.GetXAxis();
  sf::Vertex redLine[] = {
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(xf.p), sf::Color::Red),
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(xAxis), sf::Color::Red)};

  // You might notice that the ordinate(Y axis) points downward unlike the one
  // in Box2D testbed
  // That's because the ordinate in SFML coordinate system points downward while
  // the OpenGL(testbed) points upward
  /*b2Vec2 yAxis(b2Vec2(xf.p.x + (lineLength * -xf.q.s), xf.p.y + (lineLength *
   * xf.q.c)));*/
  b2Vec2 yAxis = xf.p + lineLength * xf.q.GetYAxis();
  sf::Vertex greenLine[] = {
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(xf.p), sf::Color::Green),
      sf::Vertex(SFMLDebugDraw::B2VecToSFVec(yAxis), sf::Color::Green)};

  m_window->draw(redLine, 2, sf::Lines);
  m_window->draw(greenLine, 2, sf::Lines);
}