diff options
Diffstat (limited to 'intern/cycles/kernel/svm/svm_ies.h')
| -rw-r--r-- | intern/cycles/kernel/svm/svm_ies.h | 149 |
1 files changed, 79 insertions, 70 deletions
diff --git a/intern/cycles/kernel/svm/svm_ies.h b/intern/cycles/kernel/svm/svm_ies.h index 6130c3348b0..9434c0c5505 100644 --- a/intern/cycles/kernel/svm/svm_ies.h +++ b/intern/cycles/kernel/svm/svm_ies.h @@ -18,93 +18,102 @@ CCL_NAMESPACE_BEGIN /* IES Light */ -ccl_device_inline float interpolate_ies_vertical(KernelGlobals *kg, int ofs, int v, int v_num, float v_frac, int h) +ccl_device_inline float interpolate_ies_vertical( + KernelGlobals *kg, int ofs, int v, int v_num, float v_frac, int h) { - /* Since lookups are performed in spherical coordinates, clamping the coordinates at the low end of v - * (corresponding to the north pole) would result in artifacts. - * The proper way of dealing with this would be to lookup the corresponding value on the other side of the pole, - * but since the horizontal coordinates might be nonuniform, this would require yet another interpolation. - * Therefore, the assumtion is made that the light is going to be symmetrical, which means that we can just take - * the corresponding value at the current horizontal coordinate. */ - -#define IES_LOOKUP(v) kernel_tex_fetch(__ies, ofs+h*v_num+(v)) - /* If v is zero, assume symmetry and read at v=1 instead of v=-1. */ - float a = IES_LOOKUP((v == 0)? 1 : v-1); - float b = IES_LOOKUP(v); - float c = IES_LOOKUP(v+1); - float d = IES_LOOKUP(min(v+2, v_num-1)); + /* Since lookups are performed in spherical coordinates, clamping the coordinates at the low end of v + * (corresponding to the north pole) would result in artifacts. + * The proper way of dealing with this would be to lookup the corresponding value on the other side of the pole, + * but since the horizontal coordinates might be nonuniform, this would require yet another interpolation. + * Therefore, the assumtion is made that the light is going to be symmetrical, which means that we can just take + * the corresponding value at the current horizontal coordinate. */ + +#define IES_LOOKUP(v) kernel_tex_fetch(__ies, ofs + h * v_num + (v)) + /* If v is zero, assume symmetry and read at v=1 instead of v=-1. */ + float a = IES_LOOKUP((v == 0) ? 1 : v - 1); + float b = IES_LOOKUP(v); + float c = IES_LOOKUP(v + 1); + float d = IES_LOOKUP(min(v + 2, v_num - 1)); #undef IES_LOOKUP - return cubic_interp(a, b, c, d, v_frac); + return cubic_interp(a, b, c, d, v_frac); } -ccl_device_inline float kernel_ies_interp(KernelGlobals *kg, int slot, float h_angle, float v_angle) +ccl_device_inline float kernel_ies_interp(KernelGlobals *kg, + int slot, + float h_angle, + float v_angle) { - /* Find offset of the IES data in the table. */ - int ofs = __float_as_int(kernel_tex_fetch(__ies, slot)); - if(ofs == -1) { - return 100.0f; - } - - int h_num = __float_as_int(kernel_tex_fetch(__ies, ofs++)); - int v_num = __float_as_int(kernel_tex_fetch(__ies, ofs++)); - -#define IES_LOOKUP_ANGLE_H(h) kernel_tex_fetch(__ies, ofs+(h)) -#define IES_LOOKUP_ANGLE_V(v) kernel_tex_fetch(__ies, ofs+h_num+(v)) - - /* Check whether the angle is within the bounds of the IES texture. */ - if(v_angle >= IES_LOOKUP_ANGLE_V(v_num-1)) { - return 0.0f; - } - kernel_assert(v_angle >= IES_LOOKUP_ANGLE_V(0)); - kernel_assert(h_angle >= IES_LOOKUP_ANGLE_H(0)); - kernel_assert(h_angle <= IES_LOOKUP_ANGLE_H(h_num-1)); - - /* Lookup the angles to find the table position. */ - int h_i, v_i; - /* TODO(lukas): Consider using bisection. Probably not worth it for the vast majority of IES files. */ - for(h_i = 0; IES_LOOKUP_ANGLE_H(h_i+1) < h_angle; h_i++); - for(v_i = 0; IES_LOOKUP_ANGLE_V(v_i+1) < v_angle; v_i++); - - float h_frac = inverse_lerp(IES_LOOKUP_ANGLE_H(h_i), IES_LOOKUP_ANGLE_H(h_i+1), h_angle); - float v_frac = inverse_lerp(IES_LOOKUP_ANGLE_V(v_i), IES_LOOKUP_ANGLE_V(v_i+1), v_angle); + /* Find offset of the IES data in the table. */ + int ofs = __float_as_int(kernel_tex_fetch(__ies, slot)); + if (ofs == -1) { + return 100.0f; + } + + int h_num = __float_as_int(kernel_tex_fetch(__ies, ofs++)); + int v_num = __float_as_int(kernel_tex_fetch(__ies, ofs++)); + +#define IES_LOOKUP_ANGLE_H(h) kernel_tex_fetch(__ies, ofs + (h)) +#define IES_LOOKUP_ANGLE_V(v) kernel_tex_fetch(__ies, ofs + h_num + (v)) + + /* Check whether the angle is within the bounds of the IES texture. */ + if (v_angle >= IES_LOOKUP_ANGLE_V(v_num - 1)) { + return 0.0f; + } + kernel_assert(v_angle >= IES_LOOKUP_ANGLE_V(0)); + kernel_assert(h_angle >= IES_LOOKUP_ANGLE_H(0)); + kernel_assert(h_angle <= IES_LOOKUP_ANGLE_H(h_num - 1)); + + /* Lookup the angles to find the table position. */ + int h_i, v_i; + /* TODO(lukas): Consider using bisection. Probably not worth it for the vast majority of IES files. */ + for (h_i = 0; IES_LOOKUP_ANGLE_H(h_i + 1) < h_angle; h_i++) + ; + for (v_i = 0; IES_LOOKUP_ANGLE_V(v_i + 1) < v_angle; v_i++) + ; + + float h_frac = inverse_lerp(IES_LOOKUP_ANGLE_H(h_i), IES_LOOKUP_ANGLE_H(h_i + 1), h_angle); + float v_frac = inverse_lerp(IES_LOOKUP_ANGLE_V(v_i), IES_LOOKUP_ANGLE_V(v_i + 1), v_angle); #undef IES_LOOKUP_ANGLE_H #undef IES_LOOKUP_ANGLE_V - /* Skip forward to the actual intensity data. */ - ofs += h_num+v_num; - - /* Perform cubic interpolation along the horizontal coordinate to get the intensity value. - * If h_i is zero, just wrap around since the horizontal angles always go over the full circle. - * However, the last entry (360°) equals the first one, so we need to wrap around to the one before that. */ - float a = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, (h_i == 0)? h_num-2 : h_i-1); - float b = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, h_i); - float c = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, h_i+1); - /* Same logic here, wrap around to the second element if necessary. */ - float d = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, (h_i+2 == h_num)? 1 : h_i+2); - - /* Cubic interpolation can result in negative values, so get rid of them. */ - return max(cubic_interp(a, b, c, d, h_frac), 0.0f); + /* Skip forward to the actual intensity data. */ + ofs += h_num + v_num; + + /* Perform cubic interpolation along the horizontal coordinate to get the intensity value. + * If h_i is zero, just wrap around since the horizontal angles always go over the full circle. + * However, the last entry (360°) equals the first one, so we need to wrap around to the one before that. */ + float a = interpolate_ies_vertical( + kg, ofs, v_i, v_num, v_frac, (h_i == 0) ? h_num - 2 : h_i - 1); + float b = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, h_i); + float c = interpolate_ies_vertical(kg, ofs, v_i, v_num, v_frac, h_i + 1); + /* Same logic here, wrap around to the second element if necessary. */ + float d = interpolate_ies_vertical( + kg, ofs, v_i, v_num, v_frac, (h_i + 2 == h_num) ? 1 : h_i + 2); + + /* Cubic interpolation can result in negative values, so get rid of them. */ + return max(cubic_interp(a, b, c, d, h_frac), 0.0f); } -ccl_device void svm_node_ies(KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node, int *offset) +ccl_device void svm_node_ies( + KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node, int *offset) { - uint vector_offset, strength_offset, fac_offset, dummy, slot = node.z; - decode_node_uchar4(node.y, &strength_offset, &vector_offset, &fac_offset, &dummy); + uint vector_offset, strength_offset, fac_offset, dummy, slot = node.z; + decode_node_uchar4(node.y, &strength_offset, &vector_offset, &fac_offset, &dummy); - float3 vector = stack_load_float3(stack, vector_offset); - float strength = stack_load_float_default(stack, strength_offset, node.w); + float3 vector = stack_load_float3(stack, vector_offset); + float strength = stack_load_float_default(stack, strength_offset, node.w); - vector = normalize(vector); - float v_angle = safe_acosf(-vector.z); - float h_angle = atan2f(vector.x, vector.y) + M_PI_F; + vector = normalize(vector); + float v_angle = safe_acosf(-vector.z); + float h_angle = atan2f(vector.x, vector.y) + M_PI_F; - float fac = strength * kernel_ies_interp(kg, slot, h_angle, v_angle); + float fac = strength * kernel_ies_interp(kg, slot, h_angle, v_angle); - if(stack_valid(fac_offset)) { - stack_store_float(stack, fac_offset, fac); - } + if (stack_valid(fac_offset)) { + stack_store_float(stack, fac_offset, fac); + } } CCL_NAMESPACE_END |