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/* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup obj
*/
#include "BKE_image.h"
#include "BKE_main.h"
#include "BKE_node.h"
#include "BLI_map.hh"
#include "BLI_math_vector.h"
#include "BLI_path_util.h"
#include "DNA_material_types.h"
#include "DNA_node_types.h"
#include "NOD_shader.h"
/* TODO: move eMTLSyntaxElement out of following file into a more neutral place */
#include "obj_export_io.hh"
#include "obj_import_mtl.hh"
#include "obj_import_string_utils.hh"
namespace blender::io::obj {
/**
* Set the socket's (of given ID) value to the given number(s).
* Only float value(s) can be set using this method.
*/
static void set_property_of_socket(eNodeSocketDatatype property_type,
StringRef socket_id,
Span<float> value,
bNode *r_node)
{
BLI_assert(r_node);
bNodeSocket *socket{nodeFindSocket(r_node, SOCK_IN, socket_id.data())};
BLI_assert(socket && socket->type == property_type);
switch (property_type) {
case SOCK_FLOAT: {
BLI_assert(value.size() == 1);
static_cast<bNodeSocketValueFloat *>(socket->default_value)->value = value[0];
break;
}
case SOCK_RGBA: {
/* Alpha will be added manually. It is not read from the MTL file either. */
BLI_assert(value.size() == 3);
copy_v3_v3(static_cast<bNodeSocketValueRGBA *>(socket->default_value)->value, value.data());
static_cast<bNodeSocketValueRGBA *>(socket->default_value)->value[3] = 1.0f;
break;
}
case SOCK_VECTOR: {
BLI_assert(value.size() == 3);
copy_v4_v4(static_cast<bNodeSocketValueVector *>(socket->default_value)->value,
value.data());
break;
}
default: {
BLI_assert(0);
break;
}
}
}
static bool load_texture_image_at_path(Main *bmain,
const tex_map_XX &tex_map,
bNode *r_node,
const std::string &path,
bool relative_paths)
{
Image *tex_image = BKE_image_load_exists(bmain, path.c_str());
if (!tex_image) {
fprintf(stderr, "Cannot load image file: '%s'\n", path.c_str());
return false;
}
fprintf(stderr, "Loaded image from: '%s'\n", path.c_str());
if (relative_paths) {
BLI_path_rel(tex_image->filepath, BKE_main_blendfile_path(bmain));
}
r_node->id = reinterpret_cast<ID *>(tex_image);
NodeTexImage *image = static_cast<NodeTexImage *>(r_node->storage);
image->projection = tex_map.projection_type;
return true;
}
/**
* Load image for Image Texture node and set the node properties.
* Return success if Image can be loaded successfully.
*/
static bool load_texture_image(Main *bmain,
const tex_map_XX &tex_map,
bNode *r_node,
bool relative_paths)
{
BLI_assert(r_node && r_node->type == SH_NODE_TEX_IMAGE);
/* First try treating texture path as relative. */
std::string tex_path{tex_map.mtl_dir_path + tex_map.image_path};
if (load_texture_image_at_path(bmain, tex_map, r_node, tex_path, relative_paths)) {
return true;
}
/* Then try using it directly as absolute path. */
std::string raw_path{tex_map.image_path};
if (load_texture_image_at_path(bmain, tex_map, r_node, raw_path, relative_paths)) {
return true;
}
/* Try removing quotes. */
std::string no_quote_path{tex_path};
auto end_pos = std::remove(no_quote_path.begin(), no_quote_path.end(), '"');
no_quote_path.erase(end_pos, no_quote_path.end());
if (no_quote_path != tex_path &&
load_texture_image_at_path(bmain, tex_map, r_node, no_quote_path, relative_paths)) {
return true;
}
/* Try replacing underscores with spaces. */
std::string no_underscore_path{no_quote_path};
std::replace(no_underscore_path.begin(), no_underscore_path.end(), '_', ' ');
if (no_underscore_path != no_quote_path && no_underscore_path != tex_path &&
load_texture_image_at_path(bmain, tex_map, r_node, no_underscore_path, relative_paths)) {
return true;
}
return false;
}
ShaderNodetreeWrap::ShaderNodetreeWrap(Main *bmain,
const MTLMaterial &mtl_mat,
Material *mat,
bool relative_paths)
: mtl_mat_(mtl_mat)
{
nodetree_.reset(ntreeAddTree(nullptr, "Shader Nodetree", ntreeType_Shader->idname));
bsdf_ = add_node_to_tree(SH_NODE_BSDF_PRINCIPLED);
shader_output_ = add_node_to_tree(SH_NODE_OUTPUT_MATERIAL);
set_bsdf_socket_values(mat);
add_image_textures(bmain, mat, relative_paths);
link_sockets(bsdf_, "BSDF", shader_output_, "Surface", 4);
nodeSetActive(nodetree_.get(), shader_output_);
}
/**
* Assert if caller hasn't acquired nodetree.
*/
ShaderNodetreeWrap::~ShaderNodetreeWrap()
{
if (nodetree_) {
/* nodetree's ownership must be acquired by the caller. */
nodetree_.reset();
BLI_assert(0);
}
}
bNodeTree *ShaderNodetreeWrap::get_nodetree()
{
/* If this function has been reached, we know that nodes and the nodetree
* can be added to the scene safely. */
return nodetree_.release();
}
bNode *ShaderNodetreeWrap::add_node_to_tree(const int node_type)
{
return nodeAddStaticNode(nullptr, nodetree_.get(), node_type);
}
std::pair<float, float> ShaderNodetreeWrap::set_node_locations(const int pos_x)
{
int pos_y = 0;
bool found = false;
while (true) {
for (Span<int> location : node_locations) {
if (location[0] == pos_x && location[1] == pos_y) {
pos_y += 1;
found = true;
}
else {
found = false;
}
}
if (!found) {
node_locations.append({pos_x, pos_y});
return {pos_x * node_size_, pos_y * node_size_ * 2.0 / 3.0};
}
}
}
void ShaderNodetreeWrap::link_sockets(bNode *from_node,
StringRef from_node_id,
bNode *to_node,
StringRef to_node_id,
const int from_node_pos_x)
{
std::tie(from_node->locx, from_node->locy) = set_node_locations(from_node_pos_x);
std::tie(to_node->locx, to_node->locy) = set_node_locations(from_node_pos_x + 1);
bNodeSocket *from_sock{nodeFindSocket(from_node, SOCK_OUT, from_node_id.data())};
bNodeSocket *to_sock{nodeFindSocket(to_node, SOCK_IN, to_node_id.data())};
BLI_assert(from_sock && to_sock);
nodeAddLink(nodetree_.get(), from_node, from_sock, to_node, to_sock);
}
void ShaderNodetreeWrap::set_bsdf_socket_values(Material *mat)
{
const int illum = mtl_mat_.illum;
bool do_highlight = false;
bool do_tranparency = false;
bool do_reflection = false;
bool do_glass = false;
/* See https://wikipedia.org/wiki/Wavefront_.obj_file for possible values of illum. */
switch (illum) {
case -1:
case 1:
/* Base color on, ambient on. */
break;
case 2: {
/* Highlight on. */
do_highlight = true;
break;
}
case 3: {
/* Reflection on and Ray trace on. */
do_reflection = true;
break;
}
case 4: {
/* Transparency: Glass on, Reflection: Ray trace on. */
do_glass = true;
do_reflection = true;
do_tranparency = true;
break;
}
case 5: {
/* Reflection: Fresnel on and Ray trace on. */
do_reflection = true;
break;
}
case 6: {
/* Transparency: Refraction on, Reflection: Fresnel off and Ray trace on. */
do_reflection = true;
do_tranparency = true;
break;
}
case 7: {
/* Transparency: Refraction on, Reflection: Fresnel on and Ray trace on. */
do_reflection = true;
do_tranparency = true;
break;
}
case 8: {
/* Reflection on and Ray trace off. */
do_reflection = true;
break;
}
case 9: {
/* Transparency: Glass on, Reflection: Ray trace off. */
do_glass = true;
do_reflection = false;
do_tranparency = true;
break;
}
default: {
std::cerr << "Warning! illum value = " << illum
<< "is not supported by the Principled-BSDF shader." << std::endl;
break;
}
}
/* Approximations for trying to map obj/mtl material model into
* Principled BSDF: */
/* Specular: average of Ks components. */
float specular = (mtl_mat_.Ks[0] + mtl_mat_.Ks[1] + mtl_mat_.Ks[2]) / 3;
if (specular < 0.0f) {
specular = do_highlight ? 1.0f : 0.0f;
}
/* Roughness: map 0..1000 range to 1..0 and apply non-linearity. */
float roughness;
if (mtl_mat_.Ns < 0.0f) {
roughness = do_highlight ? 0.0f : 1.0f;
}
else {
float clamped_ns = std::max(0.0f, std::min(1000.0f, mtl_mat_.Ns));
roughness = 1.0f - sqrt(clamped_ns / 1000.0f);
}
/* Metallic: average of Ka components. */
float metallic = (mtl_mat_.Ka[0] + mtl_mat_.Ka[1] + mtl_mat_.Ka[2]) / 3;
if (do_reflection) {
if (metallic < 0.0f) {
metallic = 1.0f;
}
}
else {
metallic = 0.0f;
}
float ior = mtl_mat_.Ni;
if (ior < 0) {
if (do_tranparency) {
ior = 1.0f;
}
if (do_glass) {
ior = 1.5f;
}
}
float alpha = mtl_mat_.d;
if (do_tranparency && alpha < 0) {
alpha = 1.0f;
}
float3 base_color = {mtl_mat_.Kd[0], mtl_mat_.Kd[1], mtl_mat_.Kd[2]};
if (base_color.x >= 0 && base_color.y >= 0 && base_color.z >= 0) {
set_property_of_socket(SOCK_RGBA, "Base Color", {base_color, 3}, bsdf_);
/* Viewport shading uses legacy r,g,b base color. */
mat->r = base_color.x;
mat->g = base_color.y;
mat->b = base_color.z;
}
float3 emission_color = {mtl_mat_.Ke[0], mtl_mat_.Ke[1], mtl_mat_.Ke[2]};
if (emission_color.x >= 0 && emission_color.y >= 0 && emission_color.z >= 0) {
set_property_of_socket(SOCK_RGBA, "Emission", {emission_color, 3}, bsdf_);
}
if (mtl_mat_.texture_maps.contains_as(eMTLSyntaxElement::map_Ke)) {
set_property_of_socket(SOCK_FLOAT, "Emission Strength", {1.0f}, bsdf_);
}
set_property_of_socket(SOCK_FLOAT, "Specular", {specular}, bsdf_);
set_property_of_socket(SOCK_FLOAT, "Roughness", {roughness}, bsdf_);
mat->roughness = roughness;
set_property_of_socket(SOCK_FLOAT, "Metallic", {metallic}, bsdf_);
mat->metallic = metallic;
if (ior != -1) {
set_property_of_socket(SOCK_FLOAT, "IOR", {ior}, bsdf_);
}
if (alpha != -1) {
set_property_of_socket(SOCK_FLOAT, "Alpha", {alpha}, bsdf_);
}
if (do_tranparency || (alpha >= 0.0f && alpha < 1.0f)) {
mat->blend_method = MA_BM_BLEND;
}
}
void ShaderNodetreeWrap::add_image_textures(Main *bmain, Material *mat, bool relative_paths)
{
for (const Map<const eMTLSyntaxElement, tex_map_XX>::Item texture_map :
mtl_mat_.texture_maps.items()) {
if (texture_map.value.image_path.empty()) {
/* No Image texture node of this map type can be added to this material. */
continue;
}
bNode *image_texture = add_node_to_tree(SH_NODE_TEX_IMAGE);
if (!load_texture_image(bmain, texture_map.value, image_texture, relative_paths)) {
/* Image could not be added, so don't add or link further nodes. */
continue;
}
/* Add normal map node if needed. */
bNode *normal_map = nullptr;
if (texture_map.key == eMTLSyntaxElement::map_Bump) {
normal_map = add_node_to_tree(SH_NODE_NORMAL_MAP);
const float bump = std::max(0.0f, mtl_mat_.map_Bump_strength);
set_property_of_socket(SOCK_FLOAT, "Strength", {bump}, normal_map);
}
/* Add UV mapping & coordinate nodes only if needed. */
if (texture_map.value.translation != float3(0, 0, 0) ||
texture_map.value.scale != float3(1, 1, 1)) {
bNode *mapping = add_node_to_tree(SH_NODE_MAPPING);
bNode *texture_coordinate = add_node_to_tree(SH_NODE_TEX_COORD);
set_property_of_socket(SOCK_VECTOR, "Location", {texture_map.value.translation, 3}, mapping);
set_property_of_socket(SOCK_VECTOR, "Scale", {texture_map.value.scale, 3}, mapping);
link_sockets(texture_coordinate, "UV", mapping, "Vector", 0);
link_sockets(mapping, "Vector", image_texture, "Vector", 1);
}
if (normal_map) {
link_sockets(image_texture, "Color", normal_map, "Color", 2);
link_sockets(normal_map, "Normal", bsdf_, "Normal", 3);
}
else if (texture_map.key == eMTLSyntaxElement::map_d) {
link_sockets(image_texture, "Alpha", bsdf_, texture_map.value.dest_socket_id, 2);
mat->blend_method = MA_BM_BLEND;
}
else {
link_sockets(image_texture, "Color", bsdf_, texture_map.value.dest_socket_id, 2);
}
}
}
} // namespace blender::io::obj
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