commit 60930be92d761f6742ca1858c531fd626c6a6ed8
parent 1f02ac9a68ef25e76833bb15253da15d98b45b06
Author: Vincent Forest <vincent.forest@meso-star.com>
Date: Wed, 5 Oct 2016 11:35:28 +0200
Add and test the constant Fresnel term
Diffstat:
4 files changed, 141 insertions(+), 0 deletions(-)
diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
@@ -57,6 +57,7 @@ set(SSF_FILES_SRC
ssf_bsdf.c
ssf_bxdf.c
ssf_fresnel.c
+ ssf_fresnel_constant.c
ssf_fresnel_dielectric_conductor.c
ssf_fresnel_dielectric_dielectric.c
ssf_fresnel_no_op.c
@@ -103,6 +104,7 @@ if(NOT NO_TEST)
new_test(test_ssf_bsdf)
new_test(test_ssf_bxdf)
new_test(test_ssf_fresnel)
+ new_test(test_ssf_fresnel_constant)
new_test(test_ssf_fresnel_dielectric_conductor)
new_test(test_ssf_fresnel_dielectric_dielectric)
new_test(test_ssf_fresnel_no_op)
diff --git a/src/ssf.h b/src/ssf.h
@@ -184,6 +184,9 @@ SSF_API const struct ssf_bxdf_type ssf_microfacet2_reflection;
/*******************************************************************************
* Built-in Fresnel terms
******************************************************************************/
+/* Fresnel term is a constant; Fr = k with k in [0, 1]. */
+SSF_API const struct ssf_fresnel_type ssf_fresnel_constant;
+
/* Fresnel term for perfect reflection; Fr = 1 */
SSF_API const struct ssf_fresnel_type ssf_fresnel_no_op;
@@ -390,6 +393,11 @@ ssf_fresnel_dielectric_conductor_setup
const double eta_t, /* Real part of the refraction id of the conductor */
const double k_t); /* Imaginary part of the refraction id of the conductor */
+SSF_API res_T
+ssf_fresnel_constant_setup
+ (struct ssf_fresnel* fresnel,
+ const double constant); /* in [0, 1] */
+
/*******************************************************************************
* Microfacet Distribution API - Note that by convention the outgoing direction
* `wo' and the half vector `wh' point outward the surface.
diff --git a/src/ssf_fresnel_constant.c b/src/ssf_fresnel_constant.c
@@ -0,0 +1,73 @@
+/* Copyright (C) |Meso|Star> 2016 (contact@meso-star.com)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include "ssf.h"
+#include "ssf_fresnel_c.h"
+
+struct fresnel_constant {
+ double k; /* in [0, 1] */
+};
+
+/*******************************************************************************
+ * Private functions
+ ******************************************************************************/
+static res_T
+fresnel_constant_init(struct mem_allocator* allocator, void* fresnel)
+{
+ struct fresnel_constant* f = fresnel;
+ (void)allocator;
+ ASSERT(fresnel);
+ f->k = 1; /* <=> No op */
+ return RES_OK;
+}
+
+static void
+fresnel_constant_release(void* fresnel)
+{
+ (void)fresnel;
+}
+
+static double
+fresnel_constant_eval(void* fresnel, const double cos_theta_i)
+{
+ struct fresnel_constant* f = fresnel;
+ (void)cos_theta_i;
+ return f->k;
+}
+
+/*******************************************************************************
+ * Exported symbols
+ ******************************************************************************/
+const struct ssf_fresnel_type ssf_fresnel_constant = {
+ fresnel_constant_init,
+ fresnel_constant_release,
+ fresnel_constant_eval,
+ sizeof(struct fresnel_constant),
+ ALIGNOF(struct fresnel_constant)
+};
+
+res_T
+ssf_fresnel_constant_setup(struct ssf_fresnel* fresnel, const double value)
+{
+ struct fresnel_constant* f;
+ if(!fresnel || !FRESNEL_TYPE_EQ(&fresnel->type, &ssf_fresnel_constant))
+ return RES_BAD_ARG;
+ if(value < 0 || value > 1)
+ return RES_BAD_ARG;
+ f = fresnel->data;
+ f->k = value;
+ return RES_OK;
+}
+
diff --git a/src/test_ssf_fresnel_constant.c b/src/test_ssf_fresnel_constant.c
@@ -0,0 +1,58 @@
+/* Copyright (C) |Meso|Star> 2016 (contact@meso-star.com)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#define _POSIX_C_SOURCE 200112L /* nextafter support */
+
+#include "ssf.h"
+#include "test_ssf_utils.h"
+
+int
+main(int argc, char** argv)
+{
+ struct mem_allocator allocator;
+ struct ssf_fresnel* fresnel;
+ struct ssf_fresnel* dummy;
+ (void)argc, (void)argv;
+
+ mem_init_proxy_allocator(&allocator, &mem_default_allocator);
+ CHECK(ssf_fresnel_create(&allocator, &ssf_fresnel_constant, &fresnel), RES_OK);
+ CHECK(ssf_fresnel_create(&allocator, &fresnel_dummy, &dummy), RES_OK);
+
+ CHECK(ssf_fresnel_constant_setup(NULL, -1), RES_BAD_ARG);
+ CHECK(ssf_fresnel_constant_setup(fresnel, -1), RES_BAD_ARG);
+ CHECK(ssf_fresnel_constant_setup(NULL, 0.5), RES_BAD_ARG);
+ CHECK(ssf_fresnel_constant_setup(fresnel, 0), RES_OK);
+ CHECK(ssf_fresnel_constant_setup(fresnel, 1), RES_OK);
+ CHECK(ssf_fresnel_constant_setup(fresnel, 0.5), RES_OK);
+ CHECK(ssf_fresnel_constant_setup(fresnel, nextafter(0, -1)), RES_BAD_ARG);
+ CHECK(ssf_fresnel_constant_setup(fresnel, nextafter(1, 2)), RES_BAD_ARG);
+ CHECK(ssf_fresnel_constant_setup(dummy, 0.5), RES_BAD_ARG);
+
+ CHECK(ssf_fresnel_eval(fresnel, 0), 0.5);
+ CHECK(ssf_fresnel_eval(fresnel, 1), 0.5);
+ CHECK(ssf_fresnel_eval(fresnel, 0.1234), 0.5);
+ CHECK(ssf_fresnel_constant_setup(fresnel, 0.123), RES_OK);
+ CHECK(ssf_fresnel_eval(fresnel, 0), 0.123);
+ CHECK(ssf_fresnel_eval(fresnel, 1), 0.123);
+ CHECK(ssf_fresnel_eval(fresnel, 0.25), 0.123);
+
+ CHECK(ssf_fresnel_ref_put(fresnel), RES_OK);
+ CHECK(ssf_fresnel_ref_put(dummy), RES_OK);
+
+ check_memory_allocator(&allocator);
+ mem_shutdown_proxy_allocator(&allocator);
+ CHECK(mem_allocated_size(), 0);
+ return 0;
+}
