Class EmissivePowerSampler
Synopsis
#include <Source/Falcor/Experimental/Scene/Lights/EmissivePowerSampler.h>
class dlldecl EmissivePowerSampler : public EmissiveLightSampler
Description
Sample geometry proportionally to its emissive power.
Inheritance
Ancestors: EmissiveLightSampler
Structures
| AliasTable |
Methods
| EmissivePowerSampler | ||
| ~EmissivePowerSampler | ||
| create | Creates a EmissivePowerSampler for a given scene. | |
| generateAliasTable | Generate an alias table | |
| setShaderData | Bind the light sampler data to a given shader variable. | |
| update | Updates the sampler to the current frame. |
Source
Lines 36-86 in Source/Falcor/Experimental/Scene/Lights/EmissivePowerSampler.h.
class dlldecl EmissivePowerSampler : public EmissiveLightSampler
{
public:
using SharedPtr = std::shared_ptr<EmissivePowerSampler>;
using SharedConstPtr = std::shared_ptr<const EmissivePowerSampler>;
struct AliasTable
{
float weightSum; ///< Total weight of all elements used to create the alias table
uint32_t N; ///< Number of entries in the alias table (and # elements in the buffers)
Buffer::SharedPtr fullTable; ///< A compressed/packed merged table. Max 2^24 (16 million) entries per table.
};
virtual ~EmissivePowerSampler() = default;
/** Creates a EmissivePowerSampler for a given scene.
\param[in] pRenderContext The render context.
\param[in] pScene The scene.
\param[in] options The options to override the default behavior.
*/
static SharedPtr create(RenderContext* pRenderContext, Scene::SharedPtr pScene);
/** Updates the sampler to the current frame.
\param[in] pRenderContext The render context.
\return True if the sampler was updated.
*/
virtual bool update(RenderContext* pRenderContext) override;
/** Bind the light sampler data to a given shader variable.
\param[in] var Shader variable.
\return True if successful, false otherwise.
*/
virtual bool setShaderData(const ShaderVar& var) const override;
protected:
EmissivePowerSampler(RenderContext* pRenderContext, Scene::SharedPtr pScene);
/** Generate an alias table
\param[in] weights The weights we'd like to sample each entry proportional to
\returns The alias table
*/
AliasTable generateAliasTable(std::vector<float> weights);
// Internal state
bool mNeedsRebuild = true; ///< Trigger rebuild on the next call to update(). We should always build on the first call, so the initial value is true.
LightCollection::SharedConstPtr mpLightCollection;
std::mt19937 mAliasTableRng;
AliasTable mTriangleTable;
};