solstice-solver

commit ad2f1d8fa38c922d196183cf6fc9e767509fb044
parent cfa76bd75b2b7af6a880722c87ebd519dc2dd482
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Tue,  7 Mar 2017 14:35:59 +0100

Add an the internal material_shade_rendering function

This function setups a BSDF for rendering purposes. Actually, it avoids
to use BRDFs that cannot be evaluated, and thus that cannot be used for
direct lighting.

Diffstat:
M
src/ssol_draw_pt.c
 | 
4
+++-
M
src/ssol_material.c
 | 
68
+++++++++++++++++++++++++++++++++++++++++++++++++-------------------
M
src/ssol_material_c.h
 | 
9
++++++++-

3 files changed, 60 insertions(+), 21 deletions(-)
diff --git a/src/ssol_draw_pt.c b/src/ssol_draw_pt.c
@@ -131,6 +131,7 @@ Li
   float ray_org[3];
   float ray_dir[3];
   enum ssol_side_flag side;
+  res_T res = RES_OK;
   ASSERT(scn && view && org && dir && val);
 
   ray_data.scn = scn;
@@ -173,7 +174,8 @@ Li
 
     surface_fragment_setup(&frag, o, wo, N, &hit.prim, hit.uv);
     SSF(bsdf_clear(ctx->bsdf));
-    CHECK(material_shade(mtl, &frag, 1/*TODO wavelength*/, ctx->bsdf), RES_OK);
+    res = material_shade_rendering(mtl, &frag, 1/*TODO wavelength*/, ctx->bsdf);
+    CHECK(res, RES_OK);
 
     /* Update the ray */
     ray_data.prim_from = hit.prim;
diff --git a/src/ssol_material.c b/src/ssol_material.c
@@ -78,6 +78,7 @@ mirror_shade
   (const struct ssol_material* mtl,
    const struct surface_fragment* fragment,
    const double wavelength, /* In nanometer */
+   const int rendering,
    struct ssf_bsdf* bsdf)
 {
   struct ssf_bxdf* brdf = NULL;
@@ -120,8 +121,16 @@ mirror_shade
     res = ssf_beckmann_distribution_setup(distrib, roughness);
     if(res != RES_OK) goto error;
 
-    res = ssf_bxdf_create
-      (mtl->dev->allocator, &ssf_microfacet2_reflection, &brdf);
+    /* Microfacet2 is not well suited for rendering since it cannot be
+     * evaluated and consequently it returns an invalid result for direct
+     * lighting. */
+    if(rendering) {
+      res = ssf_bxdf_create
+        (mtl->dev->allocator, &ssf_microfacet_reflection, &brdf);
+    } else {
+      res = ssf_bxdf_create
+        (mtl->dev->allocator, &ssf_microfacet2_reflection, &brdf);
+    }
     if(res != RES_OK) goto error;
     res = ssf_microfacet_reflection_setup(brdf, fresnel, distrib);
     if(res != RES_OK) goto error;
@@ -189,6 +198,34 @@ error:
   goto exit;
 }
 
+static INLINE res_T
+shade
+  (const struct ssol_material* mtl,
+   const struct surface_fragment* fragment,
+   const double wavelength, /* In nanometer */
+   const int rendering, /* Is material used for rendering */
+   struct ssf_bsdf* bsdf)
+{
+  res_T res = RES_OK;
+  ASSERT(mtl);
+
+  /* Specific material shading */
+  switch(mtl->type) {
+    case SSOL_MATERIAL_MATTE:
+      res = matte_shade(mtl, fragment, wavelength, bsdf);
+      break;
+    case SSOL_MATERIAL_MIRROR:
+      res = mirror_shade(mtl, fragment, wavelength, rendering, bsdf);
+      break;
+    case SSOL_MATERIAL_THIN_DIELECTRIC:
+      res = thin_dielectric_shade(mtl, fragment, wavelength, bsdf);
+      break;
+    case SSOL_MATERIAL_VIRTUAL: /* Nothing to shade */ break;
+    default: FATAL("Unreachable code\n"); break;
+  }
+  return res;
+}
+
 static INLINE int
 check_shader_mirror(const struct ssol_mirror_shader* shader)
 {
@@ -455,23 +492,16 @@ material_shade
    const double wavelength, /* In nanometer */
    struct ssf_bsdf* bsdf)
 {
-  res_T res = RES_OK;
-  ASSERT(mtl);
+  return shade(mtl, fragment, wavelength, 0, bsdf);
+}
 
-  /* Specific material shading */
-  switch(mtl->type) {
-    case SSOL_MATERIAL_MATTE:
-      res = matte_shade(mtl, fragment, wavelength, bsdf);
-      break;
-    case SSOL_MATERIAL_MIRROR:
-      res = mirror_shade(mtl, fragment, wavelength, bsdf);
-      break;
-    case SSOL_MATERIAL_THIN_DIELECTRIC:
-      res = thin_dielectric_shade(mtl, fragment, wavelength, bsdf);
-      break;
-    case SSOL_MATERIAL_VIRTUAL: /* Nothing to shade */ break;
-    default: FATAL("Unreachable code\n"); break;
-  }
-  return res;
+res_T
+material_shade_rendering
+  (const struct ssol_material* mtl,
+   const struct surface_fragment* fragment,
+   const double wavelength, /* In nanometer */
+   struct ssf_bsdf* bsdf)
+{
+  return shade(mtl, fragment, wavelength, 1, bsdf);
 }
 
diff --git a/src/ssol_material_c.h b/src/ssol_material_c.h
@@ -64,5 +64,12 @@ material_shade
    const double wavelength, /* In nanometer */
    struct ssf_bsdf* bsdf); /* Bidirectional Scattering Distribution Function */
 
-#endif /* SSOL_MATERIAL_C_H */
+/* Material shading for rendering purposes */
+extern LOCAL_SYM res_T
+material_shade_rendering
+  (const struct ssol_material* mtl,
+   const struct surface_fragment* fragment,
+   const double wavelength, /* In nanometer */
+   struct ssf_bsdf* bsdf); /* Bidirectional Scattering Distribution Function */
 
+#endif /* SSOL_MATERIAL_C_H */