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Diffstat (limited to 'intern/cycles/scene/shader_graph.cpp')
| -rw-r--r-- | intern/cycles/scene/shader_graph.cpp | 1239 |
1 files changed, 1239 insertions, 0 deletions
diff --git a/intern/cycles/scene/shader_graph.cpp b/intern/cycles/scene/shader_graph.cpp new file mode 100644 index 00000000000..f99dfa141f6 --- /dev/null +++ b/intern/cycles/scene/shader_graph.cpp @@ -0,0 +1,1239 @@ +/* + * Copyright 2011-2016 Blender Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#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->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 do_simplify, 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; + } + else if (do_simplify) { + simplify_settings(scene); + } +} + +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(1) << "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(1) << "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 */ + + ShaderNode *geom = NULL; + ShaderNode *texco = 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_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); +} + +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_GLASS(closure_type)) { + num_closures += 2; + } + else if (CLOSURE_IS_BSDF_MULTISCATTER(closure_type)) { + num_closures += 2; + } + else if (CLOSURE_IS_PRINCIPLED(closure_type)) { + num_closures += 8; + } + 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_HAIR_PRINCIPLED_ID) { + num_closures += 4; + } + 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 |