From 1558f5b6602ebe8ba31455b1837b2594d5c7f264 Mon Sep 17 00:00:00 2001 From: Lukas Stockner Date: Sat, 3 Sep 2016 22:40:07 +0200 Subject: Cycles: Don't run full shader evaluation for constant emission lamps Most of the time, Lamps in Cycles are just a constant emission closure, no texturing etc. Therefore, running a full shader evaluation is wasteful. To avoid that, Cycles now detects these constant emission shaders and stores their value in the lamp data along with a flag in the shader. Then, at runtime, if this flag is set, the lamp code just uses this value and only runs the full shader evaluation if it is neccessary. In scenes with a lot of lamps and with "Sample all direct/indirect" enabled, this saves up to 20% of rendering time in my tests. Reviewers: #cycles Differential Revision: https://developer.blender.org/D2193 --- intern/cycles/render/light.cpp | 12 +++++++----- intern/cycles/render/shader.cpp | 22 ++++++++++++++++++++++ intern/cycles/render/shader.h | 4 ++++ 3 files changed, 33 insertions(+), 5 deletions(-) (limited to 'intern/cycles/render') diff --git a/intern/cycles/render/light.cpp b/intern/cycles/render/light.cpp index 787e5cf07b2..c833a8b1c46 100644 --- a/intern/cycles/render/light.cpp +++ b/intern/cycles/render/light.cpp @@ -664,6 +664,11 @@ void LightManager::device_update_points(Device *device, use_light_visibility = true; } + float3 fixed_emission = make_float3(0.0f, 0.0f, 0.0f); + if(shader->is_constant_emission(&fixed_emission)) { + shader_id |= SHADER_FIXED_EMISSION; + } + if(light->type == LIGHT_POINT) { shader_id &= ~SHADER_AREA_LIGHT; @@ -677,7 +682,6 @@ void LightManager::device_update_points(Device *device, light_data[light_index*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), radius, invarea, 0.0f); light_data[light_index*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f); light_data[light_index*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f); - light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, 0.0f, 0.0f, 0.0f); } else if(light->type == LIGHT_DISTANT) { shader_id &= ~SHADER_AREA_LIGHT; @@ -698,7 +702,6 @@ void LightManager::device_update_points(Device *device, light_data[light_index*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), radius, cosangle, invarea); light_data[light_index*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f); light_data[light_index*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f); - light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, 0.0f, 0.0f, 0.0f); } else if(light->type == LIGHT_BACKGROUND) { uint visibility = scene->background->visibility; @@ -727,7 +730,6 @@ void LightManager::device_update_points(Device *device, light_data[light_index*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), 0.0f, 0.0f, 0.0f); light_data[light_index*LIGHT_SIZE + 2] = make_float4(0.0f, 0.0f, 0.0f, 0.0f); light_data[light_index*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f); - light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, 0.0f, 0.0f, 0.0f); } else if(light->type == LIGHT_AREA) { float3 axisu = light->axisu*(light->sizeu*light->size); @@ -745,7 +747,6 @@ void LightManager::device_update_points(Device *device, light_data[light_index*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), axisu.x, axisu.y, axisu.z); light_data[light_index*LIGHT_SIZE + 2] = make_float4(invarea, axisv.x, axisv.y, axisv.z); light_data[light_index*LIGHT_SIZE + 3] = make_float4(samples, dir.x, dir.y, dir.z); - light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, 0.0f, 0.0f, 0.0f); } else if(light->type == LIGHT_SPOT) { shader_id &= ~SHADER_AREA_LIGHT; @@ -765,9 +766,10 @@ void LightManager::device_update_points(Device *device, light_data[light_index*LIGHT_SIZE + 1] = make_float4(__int_as_float(shader_id), radius, invarea, spot_angle); light_data[light_index*LIGHT_SIZE + 2] = make_float4(spot_smooth, dir.x, dir.y, dir.z); light_data[light_index*LIGHT_SIZE + 3] = make_float4(samples, 0.0f, 0.0f, 0.0f); - light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, 0.0f, 0.0f, 0.0f); } + light_data[light_index*LIGHT_SIZE + 4] = make_float4(max_bounces, fixed_emission.x, fixed_emission.y, fixed_emission.z); + light_index++; } diff --git a/intern/cycles/render/shader.cpp b/intern/cycles/render/shader.cpp index 70e1443be2c..1849161ead9 100644 --- a/intern/cycles/render/shader.cpp +++ b/intern/cycles/render/shader.cpp @@ -194,6 +194,28 @@ Shader::~Shader() delete graph_bump; } +bool Shader::is_constant_emission(float3 *emission) +{ + ShaderInput *surf = graph->output()->input("Surface"); + + if(!surf->link || surf->link->parent->type != EmissionNode::node_type) { + return false; + } + + EmissionNode *node = (EmissionNode*) surf->link->parent; + + assert(node->input("Color")); + assert(node->input("Strength")); + + if(node->input("Color")->link || node->input("Strength")->link) { + return false; + } + + *emission = node->color*node->strength; + + return true; +} + void Shader::set_graph(ShaderGraph *graph_) { /* do this here already so that we can detect if mesh or object attributes diff --git a/intern/cycles/render/shader.h b/intern/cycles/render/shader.h index 696e22bc3c9..7d896652196 100644 --- a/intern/cycles/render/shader.h +++ b/intern/cycles/render/shader.h @@ -139,6 +139,10 @@ public: Shader(); ~Shader(); + /* Checks whether the shader consists of just a emission node with fixed inputs that's connected directly to the output. + * If yes, it sets the content of emission to the constant value (color * strength), which is then used for speeding up light evaluation. */ + bool is_constant_emission(float3* emission); + void set_graph(ShaderGraph *graph); void tag_update(Scene *scene); void tag_used(Scene *scene); -- cgit v1.2.3