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|
/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2007 Blender Foundation.
* All rights reserved.
*
* The Original Code is: all of this file.
*
* Contributor(s):
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file blender/nodes/shader/node_shader_tree.c
* \ingroup nodes
*/
#include <string.h>
#include "DNA_lamp_types.h"
#include "DNA_material_types.h"
#include "DNA_node_types.h"
#include "DNA_scene_types.h"
#include "DNA_space_types.h"
#include "DNA_world_types.h"
#include "DNA_linestyle_types.h"
#include "BLI_listbase.h"
#include "BLI_threads.h"
#include "BLI_utildefines.h"
#include "BLT_translation.h"
#include "BKE_context.h"
#include "BKE_linestyle.h"
#include "BKE_node.h"
#include "BKE_scene.h"
#include "RNA_access.h"
#include "GPU_material.h"
#include "RE_shader_ext.h"
#include "NOD_common.h"
#include "node_common.h"
#include "node_exec.h"
#include "node_util.h"
#include "node_shader_util.h"
static int shader_tree_poll(const bContext *C, bNodeTreeType *UNUSED(treetype))
{
Scene *scene = CTX_data_scene(C);
/* allow empty engine string too, this is from older versions that didn't have registerable engines yet */
return (scene->r.engine[0] == '\0' ||
STREQ(scene->r.engine, RE_engine_id_BLENDER_RENDER) ||
STREQ(scene->r.engine, RE_engine_id_BLENDER_GAME) ||
STREQ(scene->r.engine, RE_engine_id_CYCLES) ||
!BKE_scene_use_shading_nodes_custom(scene));
}
static void shader_get_from_context(const bContext *C, bNodeTreeType *UNUSED(treetype), bNodeTree **r_ntree, ID **r_id, ID **r_from)
{
SpaceNode *snode = CTX_wm_space_node(C);
Scene *scene = CTX_data_scene(C);
SceneLayer *sl = CTX_data_scene_layer(C);
Object *ob = OBACT_NEW;
if ((snode->shaderfrom == SNODE_SHADER_OBJECT) ||
(BKE_scene_use_new_shading_nodes(scene) == false))
{
if (ob) {
*r_from = &ob->id;
if (ob->type == OB_LAMP) {
*r_id = ob->data;
*r_ntree = ((Lamp *)ob->data)->nodetree;
}
else {
Material *ma = give_current_material(ob, ob->actcol);
if (ma) {
*r_id = &ma->id;
*r_ntree = ma->nodetree;
}
}
}
}
#ifdef WITH_FREESTYLE
else if (snode->shaderfrom == SNODE_SHADER_LINESTYLE) {
FreestyleLineStyle *linestyle = BKE_linestyle_active_from_scene(scene);
if (linestyle) {
*r_from = NULL;
*r_id = &linestyle->id;
*r_ntree = linestyle->nodetree;
}
}
#endif
else { /* SNODE_SHADER_WORLD */
if (scene->world) {
*r_from = NULL;
*r_id = &scene->world->id;
*r_ntree = scene->world->nodetree;
}
}
}
static void foreach_nodeclass(Scene *scene, void *calldata, bNodeClassCallback func)
{
func(calldata, NODE_CLASS_INPUT, N_("Input"));
func(calldata, NODE_CLASS_OUTPUT, N_("Output"));
if (BKE_scene_use_new_shading_nodes(scene)) {
func(calldata, NODE_CLASS_SHADER, N_("Shader"));
func(calldata, NODE_CLASS_TEXTURE, N_("Texture"));
}
func(calldata, NODE_CLASS_OP_COLOR, N_("Color"));
func(calldata, NODE_CLASS_OP_VECTOR, N_("Vector"));
func(calldata, NODE_CLASS_CONVERTOR, N_("Convertor"));
func(calldata, NODE_CLASS_SCRIPT, N_("Script"));
func(calldata, NODE_CLASS_GROUP, N_("Group"));
func(calldata, NODE_CLASS_INTERFACE, N_("Interface"));
func(calldata, NODE_CLASS_LAYOUT, N_("Layout"));
}
static void localize(bNodeTree *localtree, bNodeTree *UNUSED(ntree))
{
bNode *node, *node_next;
/* replace muted nodes and reroute nodes by internal links */
for (node = localtree->nodes.first; node; node = node_next) {
node_next = node->next;
if (node->flag & NODE_MUTED || node->type == NODE_REROUTE) {
nodeInternalRelink(localtree, node);
nodeFreeNode(localtree, node);
}
}
}
static void local_sync(bNodeTree *localtree, bNodeTree *ntree)
{
BKE_node_preview_sync_tree(ntree, localtree);
}
static void local_merge(bNodeTree *localtree, bNodeTree *ntree)
{
BKE_node_preview_merge_tree(ntree, localtree, true);
}
static void update(bNodeTree *ntree)
{
ntreeSetOutput(ntree);
ntree_update_reroute_nodes(ntree);
if (ntree->update & NTREE_UPDATE_NODES) {
/* clean up preview cache, in case nodes have been removed */
BKE_node_preview_remove_unused(ntree);
}
}
bNodeTreeType *ntreeType_Shader;
void register_node_tree_type_sh(void)
{
bNodeTreeType *tt = ntreeType_Shader = MEM_callocN(sizeof(bNodeTreeType), "shader node tree type");
tt->type = NTREE_SHADER;
strcpy(tt->idname, "ShaderNodeTree");
strcpy(tt->ui_name, "Shader");
tt->ui_icon = 0; /* defined in drawnode.c */
strcpy(tt->ui_description, "Shader nodes");
tt->foreach_nodeclass = foreach_nodeclass;
tt->localize = localize;
tt->local_sync = local_sync;
tt->local_merge = local_merge;
tt->update = update;
tt->poll = shader_tree_poll;
tt->get_from_context = shader_get_from_context;
tt->ext.srna = &RNA_ShaderNodeTree;
ntreeTypeAdd(tt);
}
/* GPU material from shader nodes */
static void ntree_shader_link_builtin_normal(bNodeTree *ntree,
bNode *node_from,
bNodeSocket *socket_from,
bNode *displacement_node,
bNodeSocket *displacement_socket);
/* Find an output node of the shader tree.
*
* NOTE: it will only return output which is NOT in the group, which isn't how
* render engines works but it's how the GPU shader compilation works. This we
* can change in the future and make it a generic function, but for now it stays
* private here.
*/
static bNode *ntree_shader_output_node(bNodeTree *ntree)
{
/* Make sure we only have single node tagged as output. */
ntreeSetOutput(ntree);
for (bNode *node = ntree->nodes.first; node != NULL; node = node->next) {
if (node->flag & NODE_DO_OUTPUT) {
return node;
}
}
return NULL;
}
/* Find socket with a specified identifier. */
static bNodeSocket *ntree_shader_node_find_socket(ListBase *sockets,
const char *identifier)
{
for (bNodeSocket *sock = sockets->first; sock != NULL; sock = sock->next) {
if (STREQ(sock->identifier, identifier)) {
return sock;
}
}
return NULL;
}
/* Find input socket with a specified identifier. */
static bNodeSocket *ntree_shader_node_find_input(bNode *node,
const char *identifier)
{
return ntree_shader_node_find_socket(&node->inputs, identifier);
}
/* Find output socket with a specified identifier. */
static bNodeSocket *ntree_shader_node_find_output(bNode *node,
const char *identifier)
{
return ntree_shader_node_find_socket(&node->outputs, identifier);
}
/* Check whether shader has a displacement.
*
* Will also return a node and it's socket which is connected to a displacement
* output. Additionally, link which is attached to the displacement output is
* also returned.
*/
static bool ntree_shader_has_displacement(bNodeTree *ntree,
bNode **r_node,
bNodeSocket **r_socket,
bNodeLink **r_link)
{
bNode *output_node = ntree_shader_output_node(ntree);
if (output_node == NULL) {
/* We can't have displacement without output node, apparently. */
return false;
}
/* Make sure sockets links pointers are correct. */
ntreeUpdateTree(G.main, ntree);
bNodeSocket *displacement = ntree_shader_node_find_input(output_node,
"Displacement");
if (displacement == NULL) {
/* Non-cycles node is used as an output. */
return false;
}
if (displacement->link != NULL) {
*r_node = displacement->link->fromnode;
*r_socket = displacement->link->fromsock;
*r_link = displacement->link;
}
return displacement->link != NULL;
}
static bool ntree_shader_relink_node_normal(bNodeTree *ntree,
bNode *node,
bNode *node_from,
bNodeSocket *socket_from)
{
bNodeSocket *sock = ntree_shader_node_find_input(node, "Normal");
/* TODO(sergey): Can we do something smarter here than just a name-based
* matching?
*/
if (sock == NULL) {
/* There's no Normal input, nothing to link. */
return false;
}
if (sock->link != NULL) {
/* Something is linked to the normal input already. can't
* use other input for that.
*/
return false;
}
/* Create connection between specified node and the normal input. */
nodeAddLink(ntree, node_from, socket_from, node, sock);
return true;
}
static void ntree_shader_link_builtin_group_normal(
bNodeTree *ntree,
bNode *group_node,
bNode *node_from,
bNodeSocket *socket_from,
bNode *displacement_node,
bNodeSocket *displacement_socket)
{
bNodeTree *group_ntree = (bNodeTree *)group_node->id;
/* Create input socket to plug displacement connection to. */
bNodeSocket *group_normal_socket =
ntreeAddSocketInterface(group_ntree,
SOCK_IN,
"NodeSocketVector",
"Normal");
/* Need to update tree so all node instances nodes gets proper sockets. */
bNode *group_input_node = ntreeFindType(group_ntree, NODE_GROUP_INPUT);
node_group_verify(ntree, group_node, &group_ntree->id);
if (group_input_node)
node_group_input_verify(group_ntree, group_input_node, &group_ntree->id);
ntreeUpdateTree(G.main, group_ntree);
/* Assumes sockets are always added at the end. */
bNodeSocket *group_node_normal_socket = group_node->inputs.last;
if (displacement_node == group_node) {
/* If displacement is coming from this node group we need to perform
* some internal re-linking in order to avoid cycles.
*/
bNode *group_output_node = ntreeFindType(group_ntree, NODE_GROUP_OUTPUT);
BLI_assert(group_output_node != NULL);
bNodeSocket *group_output_node_displacement_socket =
nodeFindSocket(group_output_node,
SOCK_IN,
displacement_socket->identifier);
bNodeLink *group_displacement_link = group_output_node_displacement_socket->link;
if (group_displacement_link == NULL) {
/* Displacement output is not connected to anything, can just stop
* right away.
*/
return;
}
/* This code is similar to ntree_shader_relink_displacement() */
bNode *group_displacement_node = group_displacement_link->fromnode;
bNodeSocket *group_displacement_socket = group_displacement_link->fromsock;
/* Create and link bump node.
* Can't re-use bump node from parent tree because it'll cause cycle.
*/
bNode *bump_node = nodeAddStaticNode(NULL, group_ntree, SH_NODE_BUMP);
bNodeSocket *bump_input_socket = ntree_shader_node_find_input(bump_node, "Height");
bNodeSocket *bump_output_socket = ntree_shader_node_find_output(bump_node, "Normal");
BLI_assert(bump_input_socket != NULL);
BLI_assert(bump_output_socket != NULL);
nodeAddLink(group_ntree,
group_displacement_node, group_displacement_socket,
bump_node, bump_input_socket);
/* Relink normals inside of the instanced tree. */
ntree_shader_link_builtin_normal(group_ntree,
bump_node,
bump_output_socket,
group_displacement_node,
group_displacement_socket);
ntreeUpdateTree(G.main, group_ntree);
}
else if (group_input_node) {
/* Connect group node normal input. */
nodeAddLink(ntree,
node_from, socket_from,
group_node, group_node_normal_socket);
BLI_assert(group_input_node != NULL);
bNodeSocket *group_input_node_normal_socket =
nodeFindSocket(group_input_node,
SOCK_OUT,
group_normal_socket->identifier);
BLI_assert(group_input_node_normal_socket != NULL);
/* Relink normals inside of the instanced tree. */
ntree_shader_link_builtin_normal(group_ntree,
group_input_node,
group_input_node_normal_socket,
displacement_node,
displacement_socket);
ntreeUpdateTree(G.main, group_ntree);
}
}
/* Use specified node and socket as an input for unconnected normal sockets. */
static void ntree_shader_link_builtin_normal(bNodeTree *ntree,
bNode *node_from,
bNodeSocket *socket_from,
bNode *displacement_node,
bNodeSocket *displacement_socket)
{
for (bNode *node = ntree->nodes.first; node != NULL; node = node->next) {
if (node == node_from) {
/* Don't connect node itself! */
continue;
}
if (node->type == NODE_GROUP && node->id) {
/* Special re-linking for group nodes. */
ntree_shader_link_builtin_group_normal(ntree,
node,
node_from,
socket_from,
displacement_node,
displacement_socket);
continue;
}
if (ELEM(node->type, NODE_GROUP_INPUT, NODE_GROUP_OUTPUT)) {
/* Group inputs and outputs needs nothing special. */
continue;
}
ntree_shader_relink_node_normal(ntree, node, node_from, socket_from);
}
}
/* Re-link displacement output to unconnected normal sockets via bump node.
* This way material with have proper displacement in the viewport.
*/
static void ntree_shader_relink_displacement(bNodeTree *ntree,
short compatibility)
{
if (compatibility != NODE_NEW_SHADING) {
/* We can only deal with new shading system here. */
return;
}
bNode *displacement_node;
bNodeSocket *displacement_socket;
bNodeLink *displacement_link;
if (!ntree_shader_has_displacement(ntree,
&displacement_node,
&displacement_socket,
&displacement_link))
{
/* There is no displacement output connected, nothing to re-link. */
return;
}
/* We have to disconnect displacement output socket, otherwise we'll have
* cycles in the Cycles material :)
*/
nodeRemLink(ntree, displacement_link);
/* We can't connect displacement to normal directly, use bump node for that
* and hope that it gives good enough approximation.
*/
bNode *bump_node = nodeAddStaticNode(NULL, ntree, SH_NODE_BUMP);
bNodeSocket *bump_input_socket = ntree_shader_node_find_input(bump_node, "Height");
bNodeSocket *bump_output_socket = ntree_shader_node_find_output(bump_node, "Normal");
BLI_assert(bump_input_socket != NULL);
BLI_assert(bump_output_socket != NULL);
/* Connect bump node to where displacement output was originally
* connected to.
*/
nodeAddLink(ntree,
displacement_node, displacement_socket,
bump_node, bump_input_socket);
/* Connect all free-standing Normal inputs. */
ntree_shader_link_builtin_normal(ntree,
bump_node,
bump_output_socket,
displacement_node,
displacement_socket);
/* TODO(sergey): Reconnect Geometry Info->Normal sockets to the new
* bump node.
*/
/* We modified the tree, it needs to be updated now. */
ntreeUpdateTree(G.main, ntree);
}
static bool ntree_tag_ssr_bsdf_cb(bNode *fromnode, bNode *UNUSED(tonode), void *userdata, const bool UNUSED(reversed))
{
switch (fromnode->type) {
case SH_NODE_BSDF_ANISOTROPIC:
case SH_NODE_EEVEE_METALLIC:
case SH_NODE_EEVEE_SPECULAR:
case SH_NODE_BSDF_PRINCIPLED:
case SH_NODE_BSDF_GLOSSY:
fromnode->ssr_id = (*(float *)userdata);
(*(float *)userdata) += 1;
break;
default:
/* We could return false here but since we (will)
* allow the use of Closure as RGBA, we can have
* Bsdf nodes linked to other Bsdf nodes. */
break;
}
return true;
}
/* EEVEE: Scan the ntree to set the Screen Space Reflection
* layer id of every specular node.
*/
static void ntree_shader_tag_ssr_node(bNodeTree *ntree, short compatibility)
{
if (compatibility != NODE_NEWER_SHADING) {
/* We can only deal with new shading system here. */
return;
}
bNode *output_node = ntree_shader_output_node(ntree);
if (output_node == NULL) {
return;
}
/* Make sure sockets links pointers are correct. */
ntreeUpdateTree(G.main, ntree);
int lobe_count = 0;
nodeChainIter(ntree, output_node, ntree_tag_ssr_bsdf_cb, &lobe_count, true);
}
void ntreeGPUMaterialNodes(bNodeTree *ntree, GPUMaterial *mat, short compatibility)
{
/* localize tree to create links for reroute and mute */
bNodeTree *localtree = ntreeLocalize(ntree);
bNodeTreeExec *exec;
/* Perform all needed modifications on the tree in order to support
* displacement/bump mapping.
*/
ntree_shader_relink_displacement(localtree, compatibility);
ntree_shader_tag_ssr_node(localtree, compatibility);
exec = ntreeShaderBeginExecTree(localtree);
ntreeExecGPUNodes(exec, mat, 1, compatibility);
ntreeShaderEndExecTree(exec);
ntreeFreeTree(localtree);
MEM_freeN(localtree);
}
/* **************** call to switch lamploop for material node ************ */
void (*node_shader_lamp_loop)(struct ShadeInput *, struct ShadeResult *);
void set_node_shader_lamp_loop(void (*lamp_loop_func)(ShadeInput *, ShadeResult *))
{
node_shader_lamp_loop = lamp_loop_func;
}
bNodeTreeExec *ntreeShaderBeginExecTree_internal(bNodeExecContext *context, bNodeTree *ntree, bNodeInstanceKey parent_key)
{
bNodeTreeExec *exec;
bNode *node;
/* ensures only a single output node is enabled */
ntreeSetOutput(ntree);
/* common base initialization */
exec = ntree_exec_begin(context, ntree, parent_key);
/* allocate the thread stack listbase array */
exec->threadstack = MEM_callocN(BLENDER_MAX_THREADS * sizeof(ListBase), "thread stack array");
for (node = exec->nodetree->nodes.first; node; node = node->next)
node->need_exec = 1;
return exec;
}
bNodeTreeExec *ntreeShaderBeginExecTree(bNodeTree *ntree)
{
bNodeExecContext context;
bNodeTreeExec *exec;
/* XXX hack: prevent exec data from being generated twice.
* this should be handled by the renderer!
*/
if (ntree->execdata)
return ntree->execdata;
context.previews = ntree->previews;
exec = ntreeShaderBeginExecTree_internal(&context, ntree, NODE_INSTANCE_KEY_BASE);
/* XXX this should not be necessary, but is still used for cmp/sha/tex nodes,
* which only store the ntree pointer. Should be fixed at some point!
*/
ntree->execdata = exec;
return exec;
}
void ntreeShaderEndExecTree_internal(bNodeTreeExec *exec)
{
bNodeThreadStack *nts;
int a;
if (exec->threadstack) {
for (a = 0; a < BLENDER_MAX_THREADS; a++) {
for (nts = exec->threadstack[a].first; nts; nts = nts->next)
if (nts->stack) MEM_freeN(nts->stack);
BLI_freelistN(&exec->threadstack[a]);
}
MEM_freeN(exec->threadstack);
exec->threadstack = NULL;
}
ntree_exec_end(exec);
}
void ntreeShaderEndExecTree(bNodeTreeExec *exec)
{
if (exec) {
/* exec may get freed, so assign ntree */
bNodeTree *ntree = exec->nodetree;
ntreeShaderEndExecTree_internal(exec);
/* XXX clear nodetree backpointer to exec data, same problem as noted in ntreeBeginExecTree */
ntree->execdata = NULL;
}
}
/* only for Blender internal */
bool ntreeShaderExecTree(bNodeTree *ntree, ShadeInput *shi, ShadeResult *shr)
{
ShaderCallData scd;
/**
* \note: preserve material from ShadeInput for material id, nodetree execs change it
* fix for bug "[#28012] Mat ID messy with shader nodes"
*/
Material *mat = shi->mat;
bNodeThreadStack *nts = NULL;
bNodeTreeExec *exec = ntree->execdata;
int compat;
/* convert caller data to struct */
scd.shi = shi;
scd.shr = shr;
/* each material node has own local shaderesult, with optional copying */
memset(shr, 0, sizeof(ShadeResult));
/* ensure execdata is only initialized once */
if (!exec) {
BLI_lock_thread(LOCK_NODES);
if (!ntree->execdata)
ntree->execdata = ntreeShaderBeginExecTree(ntree);
BLI_unlock_thread(LOCK_NODES);
exec = ntree->execdata;
}
nts = ntreeGetThreadStack(exec, shi->thread);
compat = ntreeExecThreadNodes(exec, nts, &scd, shi->thread);
ntreeReleaseThreadStack(nts);
// \note: set material back to preserved material
shi->mat = mat;
/* better not allow negative for now */
if (shr->combined[0] < 0.0f) shr->combined[0] = 0.0f;
if (shr->combined[1] < 0.0f) shr->combined[1] = 0.0f;
if (shr->combined[2] < 0.0f) shr->combined[2] = 0.0f;
/* if compat is zero, it has been using non-compatible nodes */
return compat;
}
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