ik.h

// © Joseph Cameron - MIT License
 
#ifndef GDK_GRAPHICS_EXT_ANIMATION_IK_H
#define GDK_GRAPHICS_EXT_ANIMATION_IK_H
 
#include <gdk/graphics/ext/animation/skeleton.h>
 
#include <functional>
#include <vector>
#include <span>
 
namespace gdk::graphics::animation {
    [[nodiscard]] pose with_limb_reaching(const skeleton &aSkeleton, const pose &aPose,
        const std::size_t aUpper, const vector3_type &aTarget, const vector3_type &aPoleDirection);
 
    [[nodiscard]] pose with_limb_reaching_in_world(const skeleton &aSkeleton, const pose &aPose,
        const std::size_t aUpper, const vector3_type &aWorldTarget,
        const vector3_type &aWorldPoleDirection, const vector3_type &aCharacterPosition,
        const quaternion_type &aCharacterRotation);
 
    struct foot_arc final {
        float lowest = 0;
        float highest = 0;
 
        [[nodiscard]] float range() const { return highest - lowest; }
    };
 
    [[nodiscard]] foot_arc measure_foot_arc(const skeleton &aSkeleton, const clip &aClip,
        const std::size_t aFoot);
 
    [[nodiscard]] pose with_bone_oriented(const skeleton &aSkeleton, const pose &aPose,
        const std::size_t aBone, const quaternion_type &aWorldRotation);
 
    [[nodiscard]] pose with_bone_oriented_in_world(const skeleton &aSkeleton, const pose &aPose,
        const std::size_t aBone, const quaternion_type &aWorldRotation,
        const quaternion_type &aCharacterRotation);
 
    [[nodiscard]] float stance_weight(const foot_arc &aArc, const float aFootHeight,
        const float aBand = 0.25f);
 
    [[nodiscard]] float pelvis_lift(std::span<const matrix4x4_type> aWorld,
        std::span<const std::size_t> aFeet, const vector3_type &aCharacterPosition,
        const quaternion_type &aCharacterRotation,
        const std::function<float(float, float)> &aGroundHeight);
}
 
#endif