blender/intern/cycles/scene/shader_graph.cpp
Brecht Van Lommel 15d316a51a Fix #113777: Cycles IES texture not working for sphere lights
This was a regression after the sphere light changes, where the normal
now is the normal along the geometry of the light and no longer suitable
for the IES texture direction.

This not only fixes point lights with non-zero radius, but makes the IES
texture direction work consistently across light types and meshes,
always rotated by the object transform.
2023-10-18 20:40:07 +02:00

1288 lines
36 KiB
C++

/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
*
* SPDX-License-Identifier: Apache-2.0 */
#include "scene/shader_graph.h"
#include "scene/attribute.h"
#include "scene/constant_fold.h"
#include "scene/scene.h"
#include "scene/shader.h"
#include "scene/shader_nodes.h"
#include "util/algorithm.h"
#include "util/foreach.h"
#include "util/log.h"
#include "util/md5.h"
#include "util/queue.h"
CCL_NAMESPACE_BEGIN
namespace {
bool check_node_inputs_has_links(const ShaderNode *node)
{
foreach (const ShaderInput *in, node->inputs) {
if (in->link) {
return true;
}
}
return false;
}
bool check_node_inputs_traversed(const ShaderNode *node, const ShaderNodeSet &done)
{
foreach (const ShaderInput *in, node->inputs) {
if (in->link) {
if (done.find(in->link->parent) == done.end()) {
return false;
}
}
}
return true;
}
} /* namespace */
/* Sockets */
void ShaderInput::disconnect()
{
if (link) {
link->links.erase(remove(link->links.begin(), link->links.end(), this), link->links.end());
}
link = NULL;
}
void ShaderOutput::disconnect()
{
foreach (ShaderInput *sock, links) {
sock->link = NULL;
}
links.clear();
}
/* Node */
ShaderNode::ShaderNode(const NodeType *type) : Node(type)
{
name = type->name;
id = -1;
bump = SHADER_BUMP_NONE;
special_type = SHADER_SPECIAL_TYPE_NONE;
create_inputs_outputs(type);
}
ShaderNode::~ShaderNode()
{
foreach (ShaderInput *socket, inputs)
delete socket;
foreach (ShaderOutput *socket, outputs)
delete socket;
}
void ShaderNode::create_inputs_outputs(const NodeType *type)
{
foreach (const SocketType &socket, type->inputs) {
if (socket.flags & SocketType::LINKABLE) {
inputs.push_back(new ShaderInput(socket, this));
}
}
foreach (const SocketType &socket, type->outputs) {
outputs.push_back(new ShaderOutput(socket, this));
}
}
ShaderInput *ShaderNode::input(const char *name)
{
foreach (ShaderInput *socket, inputs) {
if (socket->name() == name) {
return socket;
}
}
return NULL;
}
ShaderOutput *ShaderNode::output(const char *name)
{
foreach (ShaderOutput *socket, outputs)
if (socket->name() == name) {
return socket;
}
return NULL;
}
ShaderInput *ShaderNode::input(ustring name)
{
foreach (ShaderInput *socket, inputs) {
if (socket->name() == name) {
return socket;
}
}
return NULL;
}
ShaderOutput *ShaderNode::output(ustring name)
{
foreach (ShaderOutput *socket, outputs)
if (socket->name() == name) {
return socket;
}
return NULL;
}
void ShaderNode::remove_input(ShaderInput *input)
{
assert(input->link == NULL);
delete input;
inputs.erase(remove(inputs.begin(), inputs.end(), input), inputs.end());
}
void ShaderNode::attributes(Shader *shader, AttributeRequestSet *attributes)
{
foreach (ShaderInput *input, inputs) {
if (!input->link) {
if (input->flags() & SocketType::LINK_TEXTURE_GENERATED) {
if (shader->has_surface_link()) {
attributes->add(ATTR_STD_GENERATED);
}
if (shader->has_volume) {
attributes->add(ATTR_STD_GENERATED_TRANSFORM);
}
}
else if (input->flags() & SocketType::LINK_TEXTURE_UV) {
if (shader->has_surface_link()) {
attributes->add(ATTR_STD_UV);
}
}
}
}
}
bool ShaderNode::equals(const ShaderNode &other)
{
if (type != other.type || bump != other.bump) {
return false;
}
assert(inputs.size() == other.inputs.size());
/* Compare unlinkable sockets */
foreach (const SocketType &socket, type->inputs) {
if (!(socket.flags & SocketType::LINKABLE)) {
if (!Node::equals_value(other, socket)) {
return false;
}
}
}
/* Compare linkable input sockets */
for (int i = 0; i < inputs.size(); ++i) {
ShaderInput *input_a = inputs[i], *input_b = other.inputs[i];
if (input_a->link == NULL && input_b->link == NULL) {
/* Unconnected inputs are expected to have the same value. */
if (!Node::equals_value(other, input_a->socket_type)) {
return false;
}
}
else if (input_a->link != NULL && input_b->link != NULL) {
/* Expect links are to come from the same exact socket. */
if (input_a->link != input_b->link) {
return false;
}
}
else {
/* One socket has a link and another has not, inputs can't be
* considered equal.
*/
return false;
}
}
return true;
}
/* Graph */
ShaderGraph::ShaderGraph()
{
finalized = false;
simplified = false;
num_node_ids = 0;
add(create_node<OutputNode>());
}
ShaderGraph::~ShaderGraph()
{
clear_nodes();
}
ShaderNode *ShaderGraph::add(ShaderNode *node)
{
assert(!finalized);
simplified = false;
node->id = num_node_ids++;
nodes.push_back(node);
return node;
}
OutputNode *ShaderGraph::output()
{
return (OutputNode *)nodes.front();
}
void ShaderGraph::connect(ShaderOutput *from, ShaderInput *to)
{
assert(!finalized);
assert(from && to);
if (to->link) {
fprintf(stderr, "Cycles shader graph connect: input already connected.\n");
return;
}
if (from->type() != to->type()) {
/* can't do automatic conversion from closure */
if (from->type() == SocketType::CLOSURE) {
fprintf(stderr,
"Cycles shader graph connect: can only connect closure to closure "
"(%s.%s to %s.%s).\n",
from->parent->name.c_str(),
from->name().c_str(),
to->parent->name.c_str(),
to->name().c_str());
return;
}
/* add automatic conversion node in case of type mismatch */
ShaderNode *convert;
ShaderInput *convert_in;
if (to->type() == SocketType::CLOSURE) {
EmissionNode *emission = create_node<EmissionNode>();
emission->from_auto_conversion = true;
emission->set_color(one_float3());
emission->set_strength(1.0f);
convert = add(emission);
/* Connect float inputs to Strength to save an additional Value->Color conversion. */
if (from->type() == SocketType::FLOAT) {
convert_in = convert->input("Strength");
}
else {
convert_in = convert->input("Color");
}
}
else {
convert = add(create_node<ConvertNode>(from->type(), to->type(), true));
convert_in = convert->inputs[0];
}
connect(from, convert_in);
connect(convert->outputs[0], to);
}
else {
/* types match, just connect */
to->link = from;
from->links.push_back(to);
}
}
void ShaderGraph::disconnect(ShaderOutput *from)
{
assert(!finalized);
simplified = false;
from->disconnect();
}
void ShaderGraph::disconnect(ShaderInput *to)
{
assert(!finalized);
assert(to->link);
simplified = false;
to->disconnect();
}
void ShaderGraph::relink(ShaderInput *from, ShaderInput *to)
{
ShaderOutput *out = from->link;
if (out) {
disconnect(from);
connect(out, to);
}
to->parent->copy_value(to->socket_type, *(from->parent), from->socket_type);
}
void ShaderGraph::relink(ShaderOutput *from, ShaderOutput *to)
{
/* Copy because disconnect modifies this list. */
vector<ShaderInput *> outputs = from->links;
foreach (ShaderInput *sock, outputs) {
disconnect(sock);
if (to) {
connect(to, sock);
}
}
}
void ShaderGraph::relink(ShaderNode *node, ShaderOutput *from, ShaderOutput *to)
{
simplified = false;
/* Copy because disconnect modifies this list */
vector<ShaderInput *> outputs = from->links;
/* Bypass node by moving all links from "from" to "to" */
foreach (ShaderInput *sock, node->inputs) {
if (sock->link) {
disconnect(sock);
}
}
foreach (ShaderInput *sock, outputs) {
disconnect(sock);
if (to) {
connect(to, sock);
}
}
}
void ShaderGraph::simplify(Scene *scene)
{
if (!simplified) {
expand();
default_inputs(scene->shader_manager->use_osl());
clean(scene);
refine_bump_nodes();
simplified = true;
}
}
void ShaderGraph::finalize(Scene *scene, bool do_bump, bool bump_in_object_space)
{
/* before compiling, the shader graph may undergo a number of modifications.
* currently we set default geometry shader inputs, and create automatic bump
* from displacement. a graph can be finalized only once, and should not be
* modified afterwards. */
if (!finalized) {
simplify(scene);
if (do_bump) {
bump_from_displacement(bump_in_object_space);
}
ShaderInput *surface_in = output()->input("Surface");
ShaderInput *volume_in = output()->input("Volume");
/* todo: make this work when surface and volume closures are tangled up */
if (surface_in->link) {
transform_multi_closure(surface_in->link->parent, NULL, false);
}
if (volume_in->link) {
transform_multi_closure(volume_in->link->parent, NULL, true);
}
finalized = true;
}
}
void ShaderGraph::find_dependencies(ShaderNodeSet &dependencies, ShaderInput *input)
{
/* find all nodes that this input depends on directly and indirectly */
ShaderNode *node = (input->link) ? input->link->parent : NULL;
if (node != NULL && dependencies.find(node) == dependencies.end()) {
foreach (ShaderInput *in, node->inputs)
find_dependencies(dependencies, in);
dependencies.insert(node);
}
}
void ShaderGraph::clear_nodes()
{
foreach (ShaderNode *node, nodes) {
delete_node(node);
}
nodes.clear();
}
void ShaderGraph::copy_nodes(ShaderNodeSet &nodes, ShaderNodeMap &nnodemap)
{
/* copy a set of nodes, and the links between them. the assumption is
* made that all nodes that inputs are linked to are in the set too. */
/* copy nodes */
foreach (ShaderNode *node, nodes) {
ShaderNode *nnode = node->clone(this);
nnodemap[node] = nnode;
/* create new inputs and outputs to recreate links and ensure
* that we still point to valid SocketType if the NodeType
* changed in cloning, as it does for OSL nodes */
nnode->inputs.clear();
nnode->outputs.clear();
nnode->create_inputs_outputs(nnode->type);
}
/* recreate links */
foreach (ShaderNode *node, nodes) {
foreach (ShaderInput *input, node->inputs) {
if (input->link) {
/* find new input and output */
ShaderNode *nfrom = nnodemap[input->link->parent];
ShaderNode *nto = nnodemap[input->parent];
ShaderOutput *noutput = nfrom->output(input->link->name());
ShaderInput *ninput = nto->input(input->name());
/* connect */
connect(noutput, ninput);
}
}
}
}
/* Graph simplification */
/* ******************** */
/* Remove proxy nodes.
*
* These only exists temporarily when exporting groups, and we must remove them
* early so that node->attributes() and default links do not see them.
*/
void ShaderGraph::remove_proxy_nodes()
{
vector<bool> removed(num_node_ids, false);
bool any_node_removed = false;
foreach (ShaderNode *node, nodes) {
if (node->special_type == SHADER_SPECIAL_TYPE_PROXY) {
ConvertNode *proxy = static_cast<ConvertNode *>(node);
ShaderInput *input = proxy->inputs[0];
ShaderOutput *output = proxy->outputs[0];
/* bypass the proxy node */
if (input->link) {
relink(proxy, output, input->link);
}
else {
/* Copy because disconnect modifies this list */
vector<ShaderInput *> links(output->links);
foreach (ShaderInput *to, links) {
/* Remove any auto-convert nodes too if they lead to
* sockets with an automatically set default value. */
ShaderNode *tonode = to->parent;
if (tonode->special_type == SHADER_SPECIAL_TYPE_AUTOCONVERT) {
bool all_links_removed = true;
vector<ShaderInput *> links = tonode->outputs[0]->links;
foreach (ShaderInput *autoin, links) {
if (autoin->flags() & SocketType::DEFAULT_LINK_MASK) {
disconnect(autoin);
}
else {
all_links_removed = false;
}
}
if (all_links_removed) {
removed[tonode->id] = true;
}
}
disconnect(to);
/* transfer the default input value to the target socket */
tonode->copy_value(to->socket_type, *proxy, input->socket_type);
}
}
removed[proxy->id] = true;
any_node_removed = true;
}
}
/* remove nodes */
if (any_node_removed) {
list<ShaderNode *> newnodes;
foreach (ShaderNode *node, nodes) {
if (!removed[node->id]) {
newnodes.push_back(node);
}
else {
delete_node(node);
}
}
nodes = newnodes;
}
}
/* Constant folding.
*
* Try to constant fold some nodes, and pipe result directly to
* the input socket of connected nodes.
*/
void ShaderGraph::constant_fold(Scene *scene)
{
ShaderNodeSet done, scheduled;
queue<ShaderNode *> traverse_queue;
bool has_displacement = (output()->input("Displacement")->link != NULL);
/* Schedule nodes which doesn't have any dependencies. */
foreach (ShaderNode *node, nodes) {
if (!check_node_inputs_has_links(node)) {
traverse_queue.push(node);
scheduled.insert(node);
}
}
while (!traverse_queue.empty()) {
ShaderNode *node = traverse_queue.front();
traverse_queue.pop();
done.insert(node);
foreach (ShaderOutput *output, node->outputs) {
if (output->links.size() == 0) {
continue;
}
/* Schedule node which was depending on the value,
* when possible. Do it before disconnect.
*/
foreach (ShaderInput *input, output->links) {
if (scheduled.find(input->parent) != scheduled.end()) {
/* Node might not be optimized yet but scheduled already
* by other dependencies. No need to re-schedule it.
*/
continue;
}
/* Schedule node if its inputs are fully done. */
if (check_node_inputs_traversed(input->parent, done)) {
traverse_queue.push(input->parent);
scheduled.insert(input->parent);
}
}
/* Optimize current node. */
ConstantFolder folder(this, node, output, scene);
node->constant_fold(folder);
}
}
/* Folding might have removed all nodes connected to the displacement output
* even tho there is displacement to be applied, so add in a value node if
* that happens to ensure there is still a valid graph for displacement.
*/
if (has_displacement && !output()->input("Displacement")->link) {
ColorNode *value = (ColorNode *)add(create_node<ColorNode>());
value->set_value(output()->get_displacement());
connect(value->output("Color"), output()->input("Displacement"));
}
}
/* Simplification. */
void ShaderGraph::simplify_settings(Scene *scene)
{
foreach (ShaderNode *node, nodes) {
node->simplify_settings(scene);
}
}
/* Deduplicate nodes with same settings. */
void ShaderGraph::deduplicate_nodes()
{
/* NOTES:
* - Deduplication happens for nodes which has same exact settings and same
* exact input links configuration (either connected to same output or has
* the same exact default value).
* - Deduplication happens in the bottom-top manner, so we know for fact that
* all traversed nodes are either can not be deduplicated at all or were
* already deduplicated.
*/
ShaderNodeSet scheduled, done;
map<ustring, ShaderNodeSet> candidates;
queue<ShaderNode *> traverse_queue;
int num_deduplicated = 0;
/* Schedule nodes which doesn't have any dependencies. */
foreach (ShaderNode *node, nodes) {
if (!check_node_inputs_has_links(node)) {
traverse_queue.push(node);
scheduled.insert(node);
}
}
while (!traverse_queue.empty()) {
ShaderNode *node = traverse_queue.front();
traverse_queue.pop();
done.insert(node);
/* Schedule the nodes which were depending on the current node. */
bool has_output_links = false;
foreach (ShaderOutput *output, node->outputs) {
foreach (ShaderInput *input, output->links) {
has_output_links = true;
if (scheduled.find(input->parent) != scheduled.end()) {
/* Node might not be optimized yet but scheduled already
* by other dependencies. No need to re-schedule it.
*/
continue;
}
/* Schedule node if its inputs are fully done. */
if (check_node_inputs_traversed(input->parent, done)) {
traverse_queue.push(input->parent);
scheduled.insert(input->parent);
}
}
}
/* Only need to care about nodes that are actually used */
if (!has_output_links) {
continue;
}
/* Try to merge this node with another one. */
ShaderNode *merge_with = NULL;
foreach (ShaderNode *other_node, candidates[node->type->name]) {
if (node != other_node && node->equals(*other_node)) {
merge_with = other_node;
break;
}
}
/* If found an equivalent, merge; otherwise keep node for later merges */
if (merge_with != NULL) {
for (int i = 0; i < node->outputs.size(); ++i) {
relink(node, node->outputs[i], merge_with->outputs[i]);
}
num_deduplicated++;
}
else {
candidates[node->type->name].insert(node);
}
}
if (num_deduplicated > 0) {
VLOG_DEBUG << "Deduplicated " << num_deduplicated << " nodes.";
}
}
/* Check whether volume output has meaningful nodes, otherwise
* disconnect the output.
*/
void ShaderGraph::verify_volume_output()
{
/* Check whether we can optimize the whole volume graph out. */
ShaderInput *volume_in = output()->input("Volume");
if (volume_in->link == NULL) {
return;
}
bool has_valid_volume = false;
ShaderNodeSet scheduled;
queue<ShaderNode *> traverse_queue;
/* Schedule volume output. */
traverse_queue.push(volume_in->link->parent);
scheduled.insert(volume_in->link->parent);
/* Traverse down the tree. */
while (!traverse_queue.empty()) {
ShaderNode *node = traverse_queue.front();
traverse_queue.pop();
/* Node is fully valid for volume, can't optimize anything out. */
if (node->has_volume_support()) {
has_valid_volume = true;
break;
}
foreach (ShaderInput *input, node->inputs) {
if (input->link == NULL) {
continue;
}
if (scheduled.find(input->link->parent) != scheduled.end()) {
continue;
}
traverse_queue.push(input->link->parent);
scheduled.insert(input->link->parent);
}
}
if (!has_valid_volume) {
VLOG_DEBUG << "Disconnect meaningless volume output.";
disconnect(volume_in->link);
}
}
void ShaderGraph::break_cycles(ShaderNode *node, vector<bool> &visited, vector<bool> &on_stack)
{
visited[node->id] = true;
on_stack[node->id] = true;
foreach (ShaderInput *input, node->inputs) {
if (input->link) {
ShaderNode *depnode = input->link->parent;
if (on_stack[depnode->id]) {
/* break cycle */
disconnect(input);
fprintf(stderr, "Cycles shader graph: detected cycle in graph, connection removed.\n");
}
else if (!visited[depnode->id]) {
/* visit dependencies */
break_cycles(depnode, visited, on_stack);
}
}
}
on_stack[node->id] = false;
}
void ShaderGraph::compute_displacement_hash()
{
/* Compute hash of all nodes linked to displacement, to detect if we need
* to recompute displacement when shader nodes change. */
ShaderInput *displacement_in = output()->input("Displacement");
if (!displacement_in->link) {
displacement_hash = "";
return;
}
ShaderNodeSet nodes_displace;
find_dependencies(nodes_displace, displacement_in);
MD5Hash md5;
foreach (ShaderNode *node, nodes_displace) {
node->hash(md5);
foreach (ShaderInput *input, node->inputs) {
int link_id = (input->link) ? input->link->parent->id : 0;
md5.append((uint8_t *)&link_id, sizeof(link_id));
md5.append((input->link) ? input->link->name().c_str() : "");
}
if (node->special_type == SHADER_SPECIAL_TYPE_OSL) {
/* Hash takes into account socket values, to detect changes
* in the code of the node we need an exception. */
OSLNode *oslnode = static_cast<OSLNode *>(node);
md5.append(oslnode->bytecode_hash);
}
}
displacement_hash = md5.get_hex();
}
void ShaderGraph::clean(Scene *scene)
{
/* Graph simplification */
/* NOTE: Remove proxy nodes was already done. */
constant_fold(scene);
simplify_settings(scene);
deduplicate_nodes();
verify_volume_output();
/* we do two things here: find cycles and break them, and remove unused
* nodes that don't feed into the output. how cycles are broken is
* undefined, they are invalid input, the important thing is to not crash */
vector<bool> visited(num_node_ids, false);
vector<bool> on_stack(num_node_ids, false);
/* break cycles */
break_cycles(output(), visited, on_stack);
foreach (ShaderNode *node, nodes) {
if (node->special_type == SHADER_SPECIAL_TYPE_OUTPUT_AOV) {
break_cycles(node, visited, on_stack);
}
}
/* disconnect unused nodes */
foreach (ShaderNode *node, nodes) {
if (!visited[node->id]) {
foreach (ShaderInput *to, node->inputs) {
ShaderOutput *from = to->link;
if (from) {
to->link = NULL;
from->links.erase(remove(from->links.begin(), from->links.end(), to), from->links.end());
}
}
}
}
/* remove unused nodes */
list<ShaderNode *> newnodes;
foreach (ShaderNode *node, nodes) {
if (visited[node->id]) {
newnodes.push_back(node);
}
else {
delete_node(node);
}
}
nodes = newnodes;
}
void ShaderGraph::expand()
{
/* Call expand on all nodes, to generate additional nodes. */
foreach (ShaderNode *node, nodes) {
node->expand(this);
}
}
void ShaderGraph::default_inputs(bool do_osl)
{
/* nodes can specify default texture coordinates, for now we give
* everything the position by default, except for the sky texture */
GeometryNode *geom = NULL;
TextureCoordinateNode *texco = NULL;
VectorTransformNode *normal_transform = NULL;
foreach (ShaderNode *node, nodes) {
foreach (ShaderInput *input, node->inputs) {
if (!input->link && (!(input->flags() & SocketType::OSL_INTERNAL) || do_osl)) {
if (input->flags() & SocketType::LINK_TEXTURE_GENERATED) {
if (!texco) {
texco = create_node<TextureCoordinateNode>();
}
connect(texco->output("Generated"), input);
}
if (input->flags() & SocketType::LINK_TEXTURE_NORMAL) {
if (!texco) {
texco = create_node<TextureCoordinateNode>();
}
connect(texco->output("Normal"), input);
}
else if (input->flags() & SocketType::LINK_TEXTURE_UV) {
if (!texco) {
texco = create_node<TextureCoordinateNode>();
}
connect(texco->output("UV"), input);
}
else if (input->flags() & SocketType::LINK_TEXTURE_INCOMING) {
if (!geom) {
geom = create_node<GeometryNode>();
}
if (!normal_transform) {
normal_transform = create_node<VectorTransformNode>();
normal_transform->set_transform_type(NODE_VECTOR_TRANSFORM_TYPE_NORMAL);
normal_transform->set_convert_from(NODE_VECTOR_TRANSFORM_CONVERT_SPACE_WORLD);
normal_transform->set_convert_to(NODE_VECTOR_TRANSFORM_CONVERT_SPACE_OBJECT);
connect(geom->output("Incoming"), normal_transform->input("Vector"));
}
connect(normal_transform->output("Vector"), input);
}
else if (input->flags() & SocketType::LINK_INCOMING) {
if (!geom) {
geom = create_node<GeometryNode>();
}
connect(geom->output("Incoming"), input);
}
else if (input->flags() & SocketType::LINK_NORMAL) {
if (!geom) {
geom = create_node<GeometryNode>();
}
connect(geom->output("Normal"), input);
}
else if (input->flags() & SocketType::LINK_POSITION) {
if (!geom) {
geom = create_node<GeometryNode>();
}
connect(geom->output("Position"), input);
}
else if (input->flags() & SocketType::LINK_TANGENT) {
if (!geom) {
geom = create_node<GeometryNode>();
}
connect(geom->output("Tangent"), input);
}
}
}
}
if (geom) {
add(geom);
}
if (texco) {
add(texco);
}
if (normal_transform) {
add(normal_transform);
}
}
void ShaderGraph::refine_bump_nodes()
{
/* We transverse the node graph looking for bump nodes, when we find them,
* like in bump_from_displacement(), we copy the sub-graph defined from "bump"
* input to the inputs "center","dx" and "dy" What is in "bump" input is moved
* to "center" input. */
foreach (ShaderNode *node, nodes) {
if (node->special_type == SHADER_SPECIAL_TYPE_BUMP && node->input("Height")->link) {
ShaderInput *bump_input = node->input("Height");
ShaderNodeSet nodes_bump;
/* Make 2 extra copies of the subgraph defined in Bump input. */
ShaderNodeMap nodes_dx;
ShaderNodeMap nodes_dy;
/* Find dependencies for the given input. */
find_dependencies(nodes_bump, bump_input);
copy_nodes(nodes_bump, nodes_dx);
copy_nodes(nodes_bump, nodes_dy);
/* Mark nodes to indicate they are use for bump computation, so
* that any texture coordinates are shifted by dx/dy when sampling. */
foreach (ShaderNode *node, nodes_bump)
node->bump = SHADER_BUMP_CENTER;
foreach (NodePair &pair, nodes_dx)
pair.second->bump = SHADER_BUMP_DX;
foreach (NodePair &pair, nodes_dy)
pair.second->bump = SHADER_BUMP_DY;
ShaderOutput *out = bump_input->link;
ShaderOutput *out_dx = nodes_dx[out->parent]->output(out->name());
ShaderOutput *out_dy = nodes_dy[out->parent]->output(out->name());
connect(out_dx, node->input("SampleX"));
connect(out_dy, node->input("SampleY"));
/* Add generated nodes. */
foreach (NodePair &pair, nodes_dx)
add(pair.second);
foreach (NodePair &pair, nodes_dy)
add(pair.second);
/* Connect what is connected is bump to sample-center input. */
connect(out, node->input("SampleCenter"));
/* Bump input is just for connectivity purpose for the graph input,
* we re-connected this input to sample-center, so lets disconnect it
* from bump input. */
disconnect(bump_input);
}
}
}
void ShaderGraph::bump_from_displacement(bool use_object_space)
{
/* generate bump mapping automatically from displacement. bump mapping is
* done using a 3-tap filter, computing the displacement at the center,
* and two other positions shifted by ray differentials.
*
* since the input to displacement is a node graph, we need to ensure that
* all texture coordinates use are shift by the ray differentials. for this
* reason we make 3 copies of the node subgraph defining the displacement,
* with each different geometry and texture coordinate nodes that generate
* different shifted coordinates.
*
* these 3 displacement values are then fed into the bump node, which will
* output the perturbed normal. */
ShaderInput *displacement_in = output()->input("Displacement");
if (!displacement_in->link) {
return;
}
/* find dependencies for the given input */
ShaderNodeSet nodes_displace;
find_dependencies(nodes_displace, displacement_in);
/* copy nodes for 3 bump samples */
ShaderNodeMap nodes_center;
ShaderNodeMap nodes_dx;
ShaderNodeMap nodes_dy;
copy_nodes(nodes_displace, nodes_center);
copy_nodes(nodes_displace, nodes_dx);
copy_nodes(nodes_displace, nodes_dy);
/* mark nodes to indicate they are use for bump computation, so
* that any texture coordinates are shifted by dx/dy when sampling */
foreach (NodePair &pair, nodes_center)
pair.second->bump = SHADER_BUMP_CENTER;
foreach (NodePair &pair, nodes_dx)
pair.second->bump = SHADER_BUMP_DX;
foreach (NodePair &pair, nodes_dy)
pair.second->bump = SHADER_BUMP_DY;
/* add set normal node and connect the bump normal output to the set normal
* output, so it can finally set the shader normal, note we are only doing
* this for bump from displacement, this will be the only bump allowed to
* overwrite the shader normal */
ShaderNode *set_normal = add(create_node<SetNormalNode>());
/* add bump node and connect copied graphs to it */
BumpNode *bump = (BumpNode *)add(create_node<BumpNode>());
bump->set_use_object_space(use_object_space);
bump->set_distance(1.0f);
ShaderOutput *out = displacement_in->link;
ShaderOutput *out_center = nodes_center[out->parent]->output(out->name());
ShaderOutput *out_dx = nodes_dx[out->parent]->output(out->name());
ShaderOutput *out_dy = nodes_dy[out->parent]->output(out->name());
/* convert displacement vector to height */
VectorMathNode *dot_center = (VectorMathNode *)add(create_node<VectorMathNode>());
VectorMathNode *dot_dx = (VectorMathNode *)add(create_node<VectorMathNode>());
VectorMathNode *dot_dy = (VectorMathNode *)add(create_node<VectorMathNode>());
dot_center->set_math_type(NODE_VECTOR_MATH_DOT_PRODUCT);
dot_dx->set_math_type(NODE_VECTOR_MATH_DOT_PRODUCT);
dot_dy->set_math_type(NODE_VECTOR_MATH_DOT_PRODUCT);
GeometryNode *geom = (GeometryNode *)add(create_node<GeometryNode>());
connect(geom->output("Normal"), dot_center->input("Vector2"));
connect(geom->output("Normal"), dot_dx->input("Vector2"));
connect(geom->output("Normal"), dot_dy->input("Vector2"));
connect(out_center, dot_center->input("Vector1"));
connect(out_dx, dot_dx->input("Vector1"));
connect(out_dy, dot_dy->input("Vector1"));
connect(dot_center->output("Value"), bump->input("SampleCenter"));
connect(dot_dx->output("Value"), bump->input("SampleX"));
connect(dot_dy->output("Value"), bump->input("SampleY"));
/* connect the bump out to the set normal in: */
connect(bump->output("Normal"), set_normal->input("Direction"));
/* connect to output node */
connect(set_normal->output("Normal"), output()->input("Normal"));
/* finally, add the copied nodes to the graph. we can't do this earlier
* because we would create dependency cycles in the above loop */
foreach (NodePair &pair, nodes_center)
add(pair.second);
foreach (NodePair &pair, nodes_dx)
add(pair.second);
foreach (NodePair &pair, nodes_dy)
add(pair.second);
}
void ShaderGraph::transform_multi_closure(ShaderNode *node, ShaderOutput *weight_out, bool volume)
{
/* for SVM in multi closure mode, this transforms the shader mix/add part of
* the graph into nodes that feed weights into closure nodes. this is too
* avoid building a closure tree and then flattening it, and instead write it
* directly to an array */
if (node->special_type == SHADER_SPECIAL_TYPE_COMBINE_CLOSURE) {
ShaderInput *fin = node->input("Fac");
ShaderInput *cl1in = node->input("Closure1");
ShaderInput *cl2in = node->input("Closure2");
ShaderOutput *weight1_out, *weight2_out;
if (fin) {
/* mix closure: add node to mix closure weights */
MixClosureWeightNode *mix_node = create_node<MixClosureWeightNode>();
add(mix_node);
ShaderInput *fac_in = mix_node->input("Fac");
ShaderInput *weight_in = mix_node->input("Weight");
if (fin->link) {
connect(fin->link, fac_in);
}
else {
mix_node->set_fac(node->get_float(fin->socket_type));
}
if (weight_out) {
connect(weight_out, weight_in);
}
weight1_out = mix_node->output("Weight1");
weight2_out = mix_node->output("Weight2");
}
else {
/* add closure: just pass on any weights */
weight1_out = weight_out;
weight2_out = weight_out;
}
if (cl1in->link) {
transform_multi_closure(cl1in->link->parent, weight1_out, volume);
}
if (cl2in->link) {
transform_multi_closure(cl2in->link->parent, weight2_out, volume);
}
}
else {
ShaderInput *weight_in = node->input((volume) ? "VolumeMixWeight" : "SurfaceMixWeight");
/* not a closure node? */
if (!weight_in) {
return;
}
/* already has a weight connected to it? add weights */
float weight_value = node->get_float(weight_in->socket_type);
if (weight_in->link || weight_value != 0.0f) {
MathNode *math_node = create_node<MathNode>();
add(math_node);
if (weight_in->link) {
connect(weight_in->link, math_node->input("Value1"));
}
else {
math_node->set_value1(weight_value);
}
if (weight_out) {
connect(weight_out, math_node->input("Value2"));
}
else {
math_node->set_value2(1.0f);
}
weight_out = math_node->output("Value");
if (weight_in->link) {
disconnect(weight_in);
}
}
/* connected to closure mix weight */
if (weight_out) {
connect(weight_out, weight_in);
}
else {
node->set(weight_in->socket_type, weight_value + 1.0f);
}
}
}
int ShaderGraph::get_num_closures()
{
int num_closures = 0;
foreach (ShaderNode *node, nodes) {
ClosureType closure_type = node->get_closure_type();
if (closure_type == CLOSURE_NONE_ID) {
continue;
}
else if (CLOSURE_IS_BSSRDF(closure_type)) {
num_closures += 3;
}
else if (CLOSURE_IS_BSDF_MULTISCATTER(closure_type)) {
num_closures += 2;
}
else if (CLOSURE_IS_PRINCIPLED(closure_type)) {
num_closures += 12;
}
else if (CLOSURE_IS_VOLUME(closure_type)) {
/* TODO(sergey): Verify this is still needed, since we have special minimized volume storage
* for the volume steps. */
num_closures += MAX_VOLUME_STACK_SIZE;
}
else if (closure_type == CLOSURE_BSDF_MICROFACET_BECKMANN_GLASS_ID ||
closure_type == CLOSURE_BSDF_MICROFACET_GGX_GLASS_ID ||
closure_type == CLOSURE_BSDF_HAIR_CHIANG_ID ||
closure_type == CLOSURE_BSDF_HAIR_HUANG_ID)
{
num_closures += 2;
}
else {
++num_closures;
}
}
return num_closures;
}
void ShaderGraph::dump_graph(const char *filename)
{
FILE *fd = fopen(filename, "w");
if (fd == NULL) {
printf("Error opening file for dumping the graph: %s\n", filename);
return;
}
fprintf(fd, "digraph shader_graph {\n");
fprintf(fd, "ranksep=1.5\n");
fprintf(fd, "rankdir=LR\n");
fprintf(fd, "splines=false\n");
foreach (ShaderNode *node, nodes) {
fprintf(fd, "// NODE: %p\n", node);
fprintf(fd, "\"%p\" [shape=record,label=\"{", node);
if (node->inputs.size()) {
fprintf(fd, "{");
foreach (ShaderInput *socket, node->inputs) {
if (socket != node->inputs[0]) {
fprintf(fd, "|");
}
fprintf(fd, "<IN_%p>%s", socket, socket->name().c_str());
}
fprintf(fd, "}|");
}
fprintf(fd, "%s", node->name.c_str());
if (node->bump == SHADER_BUMP_CENTER) {
fprintf(fd, " (bump:center)");
}
else if (node->bump == SHADER_BUMP_DX) {
fprintf(fd, " (bump:dx)");
}
else if (node->bump == SHADER_BUMP_DY) {
fprintf(fd, " (bump:dy)");
}
if (node->outputs.size()) {
fprintf(fd, "|{");
foreach (ShaderOutput *socket, node->outputs) {
if (socket != node->outputs[0]) {
fprintf(fd, "|");
}
fprintf(fd, "<OUT_%p>%s", socket, socket->name().c_str());
}
fprintf(fd, "}");
}
fprintf(fd, "}\"]");
}
foreach (ShaderNode *node, nodes) {
foreach (ShaderOutput *output, node->outputs) {
foreach (ShaderInput *input, output->links) {
fprintf(fd,
"// CONNECTION: OUT_%p->IN_%p (%s:%s)\n",
output,
input,
output->name().c_str(),
input->name().c_str());
fprintf(fd,
"\"%p\":\"OUT_%p\":e -> \"%p\":\"IN_%p\":w [label=\"\"]\n",
output->parent,
output,
input->parent,
input);
}
}
}
fprintf(fd, "}\n");
fclose(fd);
}
CCL_NAMESPACE_END