Differential D2573 Diff 8721 intern/cycles/render/shader.cpp

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intern/cycles/render/shader.cpp

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}		}

/* maximal slope amplitude (range that contains 99.99% of the distribution) */		/* maximal slope amplitude (range that contains 99.99% of the distribution) */
static float beckmann_table_slope_max()		static float beckmann_table_slope_max()
{		{
return 6.0;		return 6.0;
}		}


		/* MSVC 2015 needs this ugly hack to prevent a codegen bug on x86
		* see T50176 for details
		*/
		#if _MSC_VER==1900
		# define MSVC_VOLATILE volatile
		#else
		# define MSVC_VOLATILE
		#endif

/* Paper used: Importance Sampling Microfacet-Based BSDFs with the		/* Paper used: Importance Sampling Microfacet-Based BSDFs with the
* Distribution of Visible Normals. Supplemental Material 2/2.		* Distribution of Visible Normals. Supplemental Material 2/2.
*		*
* http://hal.inria.fr/docs/01/00/66/20/ANNEX/supplemental2.pdf		* http://hal.inria.fr/docs/01/00/66/20/ANNEX/supplemental2.pdf
*/		*/
static void beckmann_table_rows(float *table, int row_from, int row_to)		static void beckmann_table_rows(float *table, int row_from, int row_to)
{		{
/* allocate temporary data */		/* allocate temporary data */
const int DATA_TMP_SIZE = 512;		const int DATA_TMP_SIZE = 512;
vector<double> slope_x(DATA_TMP_SIZE);		vector<double> slope_x(DATA_TMP_SIZE);
vector<double> CDF_P22_omega_i(DATA_TMP_SIZE);		vector<double> CDF_P22_omega_i(DATA_TMP_SIZE);

/* loop over incident directions */		/* loop over incident directions */
for(int index_theta = row_from; index_theta < row_to; index_theta++) {		for(int index_theta = row_from; index_theta < row_to; index_theta++) {
/* incident vector */		/* incident vector */
const float cos_theta = index_theta / (BECKMANN_TABLE_SIZE - 1.0f);		const float cos_theta = index_theta / (BECKMANN_TABLE_SIZE - 1.0f);
const float sin_theta = safe_sqrtf(1.0f - cos_theta*cos_theta);		const float sin_theta = safe_sqrtf(1.0f - cos_theta*cos_theta);

/* for a given incident vector		/* for a given incident vector
* integrate P22_{omega_i}(x_slope, 1, 1), Eq. (10) */		* integrate P22_{omega_i}(x_slope, 1, 1), Eq. (10) */
slope_x[0] = (double)-beckmann_table_slope_max();		slope_x[0] = (double)-beckmann_table_slope_max();
CDF_P22_omega_i[0] = 0;		CDF_P22_omega_i[0] = 0;

for(int index_slope_x = 1; index_slope_x < DATA_TMP_SIZE; ++index_slope_x) {		for(MSVC_VOLATILE int index_slope_x = 1; index_slope_x < DATA_TMP_SIZE; ++index_slope_x) {
/* slope_x */		/* slope_x */
slope_x[index_slope_x] = (double)(-beckmann_table_slope_max() + 2.0f * beckmann_table_slope_max() * index_slope_x/(DATA_TMP_SIZE - 1.0f));		slope_x[index_slope_x] = (double)(-beckmann_table_slope_max() + 2.0f * beckmann_table_slope_max() * index_slope_x/(DATA_TMP_SIZE - 1.0f));

/* dot product with incident vector */		/* dot product with incident vector */
float dot_product = fmaxf(0.0f, -(float)slope_x[index_slope_x]*sin_theta + cos_theta);		float dot_product = fmaxf(0.0f, -(float)slope_x[index_slope_x]*sin_theta + cos_theta);
/* marginalize P22_{omega_i}(x_slope, 1, 1), Eq. (10) */		/* marginalize P22_{omega_i}(x_slope, 1, 1), Eq. (10) */
float P22_omega_i = 0.0f;		float P22_omega_i = 0.0f;

Show All 27 Lines	for(int index_U = 0; index_U < BECKMANN_TABLE_SIZE; ++index_U) {
/* store value */		/* store value */
table[index_U + index_theta*BECKMANN_TABLE_SIZE] = (float)(		table[index_U + index_theta*BECKMANN_TABLE_SIZE] = (float)(
interp * slope_x[index_slope_x - 1] +		interp * slope_x[index_slope_x - 1] +
(1.0 - interp) * slope_x[index_slope_x]);		(1.0 - interp) * slope_x[index_slope_x]);
}		}
}		}
}		}

		#undef MSVC_VOLATILE

static void beckmann_table_build(vector<float>& table)		static void beckmann_table_build(vector<float>& table)
{		{
table.resize(BECKMANN_TABLE_SIZE*BECKMANN_TABLE_SIZE);		table.resize(BECKMANN_TABLE_SIZE*BECKMANN_TABLE_SIZE);

/* multithreaded build */		/* multithreaded build */
TaskPool pool;		TaskPool pool;

for(int i = 0; i < BECKMANN_TABLE_SIZE; i+=8)		for(int i = 0; i < BECKMANN_TABLE_SIZE; i+=8)
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