Cycles OSL: add diffuse_ramp closure in addition to phong_ramp.

1 files changed, 96 insertions, 0 deletions

diff --git a/intern/cycles/kernel/closure/bsdf_diffuse_ramp.h b/intern/cycles/kernel/closure/bsdf_diffuse_ramp.h
new file mode 100644
index 00000000000..8a09979806a
--- /dev/null
+++ b/intern/cycles/kernel/closure/bsdf_diffuse_ramp.h
@@ -0,0 +1,96 @@
+/*
+ * Adapted from Open Shading Language with this license:
+ *
+ * Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.
+ * All Rights Reserved.
+ *
+ * Modifications Copyright 2012, Blender Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * * Neither the name of Sony Pictures Imageworks nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __BSDF_DIFFUSE_RAMP_H__
+#define __BSDF_DIFFUSE_RAMP_H__
+
+CCL_NAMESPACE_BEGIN
+
+__device float3 bsdf_diffuse_ramp_get_color(const ShaderClosure *sc, const float3 colors[8], float pos)
+{
+	int MAXCOLORS = 8;
+	
+	float npos = pos * (float)(MAXCOLORS - 1);
+	int ipos = (int)npos;
+	if (ipos >= (MAXCOLORS - 1))
+		return colors[MAXCOLORS - 1];
+	float offset = npos - (float)ipos;
+	return colors[ipos] * (1.0f - offset) + colors[ipos+1] * offset;
+}
+
+__device int bsdf_diffuse_ramp_setup(ShaderClosure *sc)
+{
+	sc->type = CLOSURE_BSDF_DIFFUSE_RAMP_ID;
+	return SD_BSDF | SD_BSDF_HAS_EVAL;
+}
+
+__device void bsdf_diffuse_ramp_blur(ShaderClosure *sc, float roughness)
+{
+}
+
+__device float3 bsdf_diffuse_ramp_eval_reflect(const ShaderClosure *sc, const float3 colors[8], const float3 I, const float3 omega_in, float *pdf)
+{
+	float3 N = sc->N;
+
+	float cos_pi = fmaxf(dot(N, omega_in), 0.0f);
+	*pdf = cos_pi * M_1_PI_F;
+	return bsdf_diffuse_ramp_get_color(sc, colors, cos_pi) * M_1_PI_F;
+}
+
+__device float3 bsdf_diffuse_ramp_eval_transmit(const ShaderClosure *sc, const float3 colors[8], const float3 I, const float3 omega_in, float *pdf)
+{
+	return make_float3(0.0f, 0.0f, 0.0f);
+}
+
+__device int bsdf_diffuse_ramp_sample(const ShaderClosure *sc, const float3 colors[8], float3 Ng, float3 I, float3 dIdx, float3 dIdy, float randu, float randv, float3 *eval, float3 *omega_in, float3 *domega_in_dx, float3 *domega_in_dy, float *pdf)
+{
+	float3 N = sc->N;
+
+	// distribution over the hemisphere
+	sample_cos_hemisphere(N, randu, randv, omega_in, pdf);
+
+	if(dot(Ng, *omega_in) > 0.0f) {
+		*eval = bsdf_diffuse_ramp_get_color(sc, colors, *pdf * M_PI_F) * M_1_PI_F;
+#ifdef __RAY_DIFFERENTIALS__
+		*domega_in_dx = (2 * dot(N, dIdx)) * N - dIdx;
+		*domega_in_dy = (2 * dot(N, dIdy)) * N - dIdy;
+#endif
+	}
+	else
+		*pdf = 0.0f;
+	
+	return LABEL_REFLECT|LABEL_DIFFUSE;
+}
+
+CCL_NAMESPACE_END
+
+#endif /* __BSDF_DIFFUSE_RAMP_H__ */