Cycles: Optimization for black world backgrounds

* If a Background node is set to a black color or zero strength,
it now gets removed from the shader graph.

* In case the graph is empty (no background node), the kernel will skip
evaluating it and save some rendertime. This can help quite a bit in scenes,
where the majority of the image consists of a black background.

Example: http://www.pasteall.org/pic/show.php?id=82650
In this case the render is ~16% faster.

Differential Revision: https://developer.blender.org/D972
This commit is contained in:
Thomas Dinges 2015-01-21 20:06:53 +01:00
parent 7165db53f2
commit cd72396797
4 changed files with 43 additions and 11 deletions

View File

@ -72,16 +72,23 @@ void Background::device_update(Device *device, DeviceScene *dscene, Scene *scene
else
kbackground->volume_shader = SHADER_NONE;
if(!(visibility & PATH_RAY_DIFFUSE))
kbackground->surface_shader |= SHADER_EXCLUDE_DIFFUSE;
if(!(visibility & PATH_RAY_GLOSSY))
kbackground->surface_shader |= SHADER_EXCLUDE_GLOSSY;
if(!(visibility & PATH_RAY_TRANSMIT))
kbackground->surface_shader |= SHADER_EXCLUDE_TRANSMIT;
if(!(visibility & PATH_RAY_VOLUME_SCATTER))
kbackground->surface_shader |= SHADER_EXCLUDE_SCATTER;
if(!(visibility & PATH_RAY_CAMERA))
kbackground->surface_shader |= SHADER_EXCLUDE_CAMERA;
/* No background node, make world shader invisible to all rays, to skip evaluation in kernel. */
if(scene->shaders[shader]->graph->nodes.size() <= 1) {
kbackground->surface_shader |= SHADER_EXCLUDE_ANY;
}
/* Background present, check visibilities */
else {
if(!(visibility & PATH_RAY_DIFFUSE))
kbackground->surface_shader |= SHADER_EXCLUDE_DIFFUSE;
if(!(visibility & PATH_RAY_GLOSSY))
kbackground->surface_shader |= SHADER_EXCLUDE_GLOSSY;
if(!(visibility & PATH_RAY_TRANSMIT))
kbackground->surface_shader |= SHADER_EXCLUDE_TRANSMIT;
if(!(visibility & PATH_RAY_VOLUME_SCATTER))
kbackground->surface_shader |= SHADER_EXCLUDE_SCATTER;
if(!(visibility & PATH_RAY_CAMERA))
kbackground->surface_shader |= SHADER_EXCLUDE_CAMERA;
}
need_update = false;
}

View File

@ -374,6 +374,28 @@ void ShaderGraph::remove_unneeded_nodes()
removed[proxy->id] = true;
any_node_removed = true;
}
else if(node->special_type == SHADER_SPECIAL_TYPE_BACKGROUND) {
BackgroundNode *bg = static_cast<BackgroundNode*>(node);
if(bg->outputs[0]->links.size()) {
/* Black color or zero strength, remove node */
if((!bg->inputs[0]->link && bg->inputs[0]->value == make_float3(0.0f, 0.0f, 0.0f)) ||
(!bg->inputs[1]->link && bg->inputs[1]->value.x == 0.0f)) {
vector<ShaderInput*> inputs = bg->outputs[0]->links;
foreach(ShaderInput *sock, bg->inputs) {
if(sock->link)
disconnect(sock);
}
foreach(ShaderInput *input, inputs)
disconnect(input);
removed[bg->id] = true;
any_node_removed = true;
}
}
}
else if(node->special_type == SHADER_SPECIAL_TYPE_MIX_CLOSURE) {
MixClosureNode *mix = static_cast<MixClosureNode*>(node);

View File

@ -79,7 +79,8 @@ enum ShaderNodeSpecialType {
SHADER_SPECIAL_TYPE_MIX_RGB, /* Only Mix subtype */
SHADER_SPECIAL_TYPE_AUTOCONVERT,
SHADER_SPECIAL_TYPE_GEOMETRY,
SHADER_SPECIAL_TYPE_SCRIPT
SHADER_SPECIAL_TYPE_SCRIPT,
SHADER_SPECIAL_TYPE_BACKGROUND,
};
/* Enum

View File

@ -1946,6 +1946,8 @@ void EmissionNode::compile(OSLCompiler& compiler)
BackgroundNode::BackgroundNode()
: ShaderNode("background")
{
special_type = SHADER_SPECIAL_TYPE_BACKGROUND;
add_input("Color", SHADER_SOCKET_COLOR, make_float3(0.8f, 0.8f, 0.8f));
add_input("Strength", SHADER_SOCKET_FLOAT, 1.0f);
add_input("SurfaceMixWeight", SHADER_SOCKET_FLOAT, 0.0f, ShaderInput::USE_SVM);