void Shape::updateOutline()
{
std::size_t count = m_vertices.getVertexCount() - 2;
m_outlineVertices.resize((count + 1) * 2);
for (std::size_t i = 0; i < count; ++i)
{
std::size_t index = i + 1;
// Get the two segments shared by the current point
Vector2f p0 = (i == 0) ? m_vertices[count].position : m_vertices[index - 1].position;
Vector2f p1 = m_vertices[index].position;
Vector2f p2 = m_vertices[index + 1].position;
// Compute their normal
Vector2f n1 = computeNormal(p0, p1);
Vector2f n2 = computeNormal(p1, p2);
// Make sure that the normals point towards the outside of the shape
// (this depends on the order in which the points were defined)
if (dotProduct(n1, m_vertices[0].position - p1) > 0)
n1 = -n1;
if (dotProduct(n2, m_vertices[0].position - p1) > 0)
n2 = -n2;
// Combine them to get the extrusion direction
float factor = 1.f + (n1.x * n2.x + n1.y * n2.y);
Vector2f normal = (n1 + n2) / factor;
// Update the outline points
m_outlineVertices[i * 2 + 0].position = p1;
m_outlineVertices[i * 2 + 1].position = p1 + normal * m_outlineThickness;
}
// Duplicate the first point at the end, to close the outline
m_outlineVertices[count * 2 + 0].position = m_outlineVertices[0].position;
m_outlineVertices[count * 2 + 1].position = m_outlineVertices[1].position;
// Update outline colors
updateOutlineColors();
// Update the shape's bounds
m_bounds = m_outlineVertices.getBounds();
}
void Shape::updateOutline()
{
unsigned int count = m_vertices.getVertexCount() - 2;
m_outlineVertices.resize((count + 1) * 2);
for (unsigned int i = 0; i < count; ++i)
{
unsigned int index = i + 1;
// Get the two segments shared by the current point
Vector2f p0 = (i == 0) ? m_vertices[count].position : m_vertices[index - 1].position;
Vector2f p1 = m_vertices[index].position;
Vector2f p2 = m_vertices[index + 1].position;
// Compute their normal
Vector2f n1 = computeNormal(p0, p1);
Vector2f n2 = computeNormal(p1, p2);
// Combine them to get the extrusion direction
float factor = 1.f + (n1.x * n2.x + n1.y * n2.y);
Vector2f normal = -(n1 + n2) / factor;
// Update the outline points
m_outlineVertices[i * 2 + 0].position = p1;
m_outlineVertices[i * 2 + 1].position = p1 + normal * m_outlineThickness;
}
// Duplicate the first point at the end, to close the outline
m_outlineVertices[count * 2 + 0].position = m_outlineVertices[0].position;
m_outlineVertices[count * 2 + 1].position = m_outlineVertices[1].position;
// Update outline colors
updateOutlineColors();
// Update the shape's bounds
m_bounds = m_outlineVertices.getBounds();
}
void Shape::setOutlineColor(const Color& color)
{
m_outlineColor = color;
updateOutlineColors();
}
