void Frustum::InitFromGLState()
{
glGetDoublev(GL_PROJECTION_MATRIX, m_projMatrix.Data());
glGetDoublev(GL_MODELVIEW_MATRIX, m_modelMatrix.Data());
matrix4x4d m = matrix4x4d(m_projMatrix) * matrix4x4d(m_modelMatrix);
InitFromMatrix(m);
}
Frustum::Frustum(float width, float height, float fovAng)
{
float fov = tan(DEG2RAD(Clamp(fovAng, FOV_MIN, FOV_MAX) / 2.0f));
float znear, zfar;
GetNearFarClipPlane(znear, zfar);
float left = fov * znear;
float top = left * height/width;
m_projMatrix = matrix4x4d::FrustumMatrix(-left, left, -top, top, znear, zfar);
m_modelMatrix = matrix4x4d::Identity();
InitFromMatrix(m_projMatrix);
}
Frustum::Frustum(float width, float height, float fovAng, float znear, float zfar)
{
//http://www.opengl.org/resources/faq/technical/transformations.htm
const float fov = tan(DEG2RAD(Clamp(fovAng, FOV_MIN, FOV_MAX) / 2.0f));
const float aspect = width/height;
const float top = znear * fov;
const float bottom = -top;
const float left = bottom * aspect;
const float right = top * aspect;
m_projMatrix = matrix4x4d::FrustumMatrix(left, right, bottom, top, znear, zfar);
m_modelMatrix = matrix4x4d::Identity();
InitFromMatrix(m_projMatrix);
}
