Files
gpu-renderer/animation.c
T

51 lines
1.3 KiB
C

#include "animation.h"
#include <assert.h>
#include <stdlib.h>
static mat4_t bone_transform(bone_t bone)
{
return mat4_mul(
mat4_translate_vec3(bone.translation),
mat4_mul(
mat4_rotate_quaternion(bone.rotation),
mat4_scale_vec3(bone.scale)));
}
static void compute_bone_matrices(
size_t bone_count, const bone_t *bones,
const mat4_t *inverse_bind_matrices, mat4_t *matrices)
{
matrices[0] = bone_transform(bones[0]);
for (unsigned i = 1; i < bone_count; ++i) {
const mat4_t transform = bone_transform(bones[i]);
assert(bones[i].parent < bone_count);
matrices[i] = mat4_mul(matrices[bones[i].parent], transform);
}
for (unsigned i = 0; i < bone_count; ++i)
matrices[i] = mat4_mul(matrices[i], inverse_bind_matrices[i]);
}
animation_state_t animation_init(const model_t *model)
{
mat4_t *bone_matrices = calloc(model->bone_count, sizeof(mat4_t));
assert(bone_matrices != nullptr);
return (animation_state_t) { .bone_matrices = bone_matrices };
}
void animation_cleanup(animation_state_t *state)
{
if (state->bone_matrices != nullptr) {
free(state->bone_matrices);
state->bone_matrices = nullptr;
}
}
void animation_update(animation_state_t state, const model_t *model)
{
compute_bone_matrices(
model->bone_count, model->bones, model->inverse_bind_matrices,
state.bone_matrices);
}