commit cf5b83c4776a3160e169fe288ebb213e8f9a80e4
parent 665a94251e0a4723d7a7cb47d6e984687f12ced0
Author: Vincent Forest <vincent.forest@meso-star.com>
Date: Mon, 2 Nov 2015 15:29:53 +0100
Begin the implementation of the thumbnail dump
Diffstat:
3 files changed, 282 insertions(+), 2 deletions(-)
diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
@@ -68,12 +68,14 @@ set(SCHIFF_FILES_SRC
schiff_args.c
schiff_geometry.c
schiff_mesh.c
- schiff_optical_properties.c)
+ schiff_optical_properties.c
+ schiff_thumbnail.c)
set(SCHIFF_FILES_INC
schiff_args.h
schiff_geometry.h
schiff_mesh.h
- schiff_optical_properties.h)
+ schiff_optical_properties.h
+ schiff_thumbnail.h)
set(SCHIFF_FILES_DOC COPYING.fr COPYING.en README.md)
# Prepend each file in the `SCHIFF_FILES_<SRC|INC>' list by the absolute
diff --git a/src/schiff_thumbnail.c b/src/schiff_thumbnail.c
@@ -0,0 +1,236 @@
+/* Copyright (C) |Meso|Star> 2015 (contact@meso-star.com)
+ *
+ * This software is governed by the CeCILL license under French law and
+ * abiding by the rules of distribution of free software. You can use,
+ * modify and/or redistribute the software under the terms of the CeCILL
+ * license as circulated by CEA, CNRS and INRIA at the following URL
+ * "http://www.cecill.info".
+ *
+ * As a counterpart to the access to the source code and rights to copy,
+ * modify and redistribute granted by the license, users are provided only
+ * with a limited warranty and the software's author, the holder of the
+ * economic rights, and the successive licensors have only limited
+ * liability.
+ *
+ * In this respect, the user's attention is drawn to the risks associated
+ * with loading, using, modifying and/or developing or reproducing the
+ * software by the user in light of its specific status of free software,
+ * that may mean that it is complicated to manipulate, and that also
+ * therefore means that it is reserved for developers and experienced
+ * professionals having in-depth computer knowledge. Users are therefore
+ * encouraged to load and test the software's suitability as regards their
+ * requirements in conditions enabling the security of their systems and/or
+ * data to be ensured and, more generally, to use and operate it in the
+ * same conditions as regards security.
+ *
+ * The fact that you are presently reading this means that you have had
+ * knowledge of the CeCILL license and that you accept its terms. */
+
+#include "schiff_thumbnail.h"
+
+#include <rsys/float2.h>
+#include <rsys/float3.h>
+#include <rsys/image.h>
+#include <rsys/stretchy_array.h>
+
+#include <star/s3d.h>
+#include <star/ssp.h>
+
+/*******************************************************************************
+ * Helper functions
+ ******************************************************************************/
+static uint16_t
+morton2D_decode(const uint32_t u32)
+{
+ uint32_t x = u32 & 0x55555555;
+ x = (x | (x >> 1)) & 0x33333333;
+ x = (x | (x >> 2)) & 0x0F0F0F0F;
+ x = (x | (x >> 4)) & 0x00FF00FF;
+ x = (x | (x >> 8)) & 0x0000FFFF;
+ return (uint16_t)x;
+}
+
+/* Compute an orthonormal basis where `dir' is the Z axis. */
+static void
+build_basis(const float dir[3], float basis[9])
+{
+ float dir_abs[3];
+ float axis_min[3];
+ int i;
+ ASSERT(dir && basis && f3_is_normalized(dir));
+
+ /* Define which axis direction is minimal and use its unit vector to compute
+ * a vector ortogonal to `dir'. This ensures that the unit vector and `dir'
+ * are not colinear and thus that their cross product is not a zero vector. */
+ FOR_EACH(i, 0, 3) dir_abs[i] = absf(dir[i]);
+ if(dir_abs[0] < dir_abs[1]) {
+ if(dir_abs[0] < dir_abs[2]) f3(axis_min, 1.f, 0.f, 0.f);
+ else f3(axis_min, 0.f, 0.f, 1.f);
+ } else {
+ if(dir_abs[1] < dir_abs[2]) f3(axis_min, 0.f, 1.f, 0.f);
+ else f3(axis_min, 0.f, 0.f, 1.f);
+ }
+
+ f3_normalize(basis + 0, f3_cross(basis + 0, dir, axis_min));
+ f3_cross(basis + 3, dir, basis + 0);
+ f3_set(basis + 6, dir);
+}
+
+/* Compute a 3x4 affine transformation from a orthonormal basis and the
+ * position of the origin */
+static FINLINE void
+build_transform
+ (const float pos[3], /* Position of the origin */
+ const float basis[9], /* Column major */
+ float transform[12]) /* Column major */
+{
+ ASSERT(pos && basis && transform);
+
+ /* The linear part of the transform matrix is the inverse of the
+ * orthonormal basis (i.e. its transpose) */
+ f3(transform + 0, basis[0], basis[3], basis[6]);
+ f3(transform + 3, basis[1], basis[4], basis[7]);
+ f3(transform + 6, basis[2], basis[5], basis[8]);
+
+ /* Affine part of the transform matrix */
+ transform[9 ] = -f3_dot(basis+0, pos);
+ transform[10] = -f3_dot(basis+3, pos);
+ transform[11] = -f3_dot(basis+6, pos);
+}
+
+static void
+draw_thumbnail
+ (struct s3d_scene* scn,
+ const size_t definition, /* Thumbnail definition */
+ const float basis[9], /* World space basis of the RT volume */
+ const float pos[3], /* World space centroid of the RT volume */
+ const float lower[3], /* Lower boundary of the RT volume */
+ const float upper[3], /* Upper boundary of the RT volume */
+ const char* name)
+{
+ const float range[2] = { 0, FLT_MAX };
+ float axis_x[3], axis_y[3], axis_z[3];
+ float plane_size[2];
+ float ray_org[3];
+ float org[3];
+ const size_t definition_adjusted = round_up_pow2(definition);
+ const float pixel_size = 1.f/(float)definition;
+ uint32_t npixels = (uint32_t)(definition_adjusted * definition_adjusted);
+ uint32_t mcode;
+ unsigned char* img = NULL;
+ ASSERT(definition && basis && pos && lower && upper && name);
+
+ /* Allocate the thumbnail buffer */
+ img = sa_add(img, definition*definition);
+ ASSERT(img != NULL);
+
+ /* Define the projection axis */
+ f2_sub(plane_size, upper, lower);
+ f3_mulf(axis_x, basis + 0, plane_size[0] * 0.5f);
+ f3_mulf(axis_y, basis + 3, plane_size[1] * 0.5f);
+ f3_set(axis_z, basis + 6);
+
+ /* Compute the origin of the projection plane */
+ f3_add(org, pos, f3_mulf(org, axis_z, lower[2]));
+
+ FOR_EACH(mcode, 0, npixels) {
+ struct s3d_hit hit;
+ size_t ipixel;
+ float sample[2], x[3], y[3];
+ uint16_t ipixel_x, ipixel_y;
+
+ /* Compute the sample position in [0, 1)^2 onto the projection plane */
+ ipixel_x = morton2D_decode(mcode);
+ if(ipixel_x > definition) continue; /* Discard out of bound pixel */
+ ipixel_y = morton2D_decode(mcode>>1);
+ if(ipixel_y > definition) continue; /* Discard out of bound pixel */
+ sample[0] = ((float)ipixel_x + 0.5f) * pixel_size;
+ sample[1] = ((float)ipixel_y + 0.5f) * pixel_size;
+
+ /* Compute the ray origin */
+ f3_mulf(x, axis_x, sample[0]*2.f - 1.f);
+ f3_mulf(y, axis_y, sample[1]*2.f - 1.f);
+ f3_add(ray_org, f3_add(ray_org, x, y), org);
+
+ S3D(scene_trace_ray(scn, ray_org, axis_z, range, &hit));
+
+ /* Simple shading */
+ ipixel = (size_t)(ipixel_y * definition + ipixel_x);
+ if(S3D_HIT_NONE(&hit)) {
+ img[ipixel] = 0;
+ } else {
+ float N[3] = {0.f,0.f,0.f};
+ float cosine;
+ f3_normalize(N, hit.normal);
+ if(0 > (cosine = f3_dot(N, axis_z))) {
+ cosine = f3_dot(f3_minus(N, N), axis_z);
+ }
+ img[ipixel] = (unsigned char)(cosine*255.f + 0.5f/*Round*/);
+ }
+ }
+ image_ppm_write(name, (int)definition, (int)definition, 1, img);
+ sa_release(img);
+}
+
+/*******************************************************************************
+ * Local functions
+ ******************************************************************************/
+void
+schiff_thumbnail
+ (struct s3d_scene* scn,
+ const size_t definition)
+{
+ struct ssp_rng* rng = NULL;
+ float lower[3], upper[3];
+ float aabb_pt[8][3];
+ float basis[9];
+ float transform[12];
+ float centroid[3];
+ float dir[4];
+ int i;
+ ASSERT(scn);
+
+ SSP(rng_create(NULL, &ssp_rng_threefry, &rng));
+ S3D(scene_get_aabb(scn, lower, upper));
+
+ /* AABB vertex layout
+ * 6-------7
+ * /' /|
+ * 2-------3 |
+ * | 4.....|.5
+ * |, |/
+ * 0-------1 */
+ f3(aabb_pt[0], lower[0], lower[1], lower[2]);
+ f3(aabb_pt[1], upper[0], lower[1], lower[2]);
+ f3(aabb_pt[2], lower[0], upper[1], lower[2]);
+ f3(aabb_pt[3], upper[0], upper[1], lower[2]);
+ f3(aabb_pt[4], lower[0], lower[1], upper[2]);
+ f3(aabb_pt[5], upper[0], lower[1], upper[2]);
+ f3(aabb_pt[6], lower[0], upper[1], upper[2]);
+ f3(aabb_pt[7], upper[0], upper[1], upper[2]);
+
+ ssp_ran_sphere_uniform(rng, dir);
+
+ /* Build the transformation matrix from world to camera space. Use the AABB
+ * centroid as the origin of the camera space. */
+ build_basis(dir, basis);
+ build_transform(centroid, basis, transform);
+
+ /* Transform the AABB from world to camera space */
+ f3_splat(lower, FLT_MAX); f3_splat(upper,-FLT_MAX);
+ FOR_EACH(i, 0, 8) {
+ f3_add(aabb_pt[i], f33_mulf3(aabb_pt[i], transform, aabb_pt[i]), transform+9);
+ f3_min(lower, lower, aabb_pt[i]);
+ f3_max(upper, upper, aabb_pt[i]);
+ }
+
+ /* Ensure an aspect ratio of 1 */
+ if(lower[0] > lower[1]) lower[1] = lower[0];
+ else lower[0] = lower[1];
+ if(upper[0] > upper[1]) upper[1] = upper[0];
+ else upper[0] = upper[1];
+
+ draw_thumbnail(scn, definition, basis, centroid, lower, upper, "pouet.ppm");
+ SSP(rng_ref_put(rng));
+}
+
diff --git a/src/schiff_thumbnail.h b/src/schiff_thumbnail.h
@@ -0,0 +1,42 @@
+/* Copyright (C) |Meso|Star> 2015 (contact@meso-star.com)
+ *
+ * This software is governed by the CeCILL license under French law and
+ * abiding by the rules of distribution of free software. You can use,
+ * modify and/or redistribute the software under the terms of the CeCILL
+ * license as circulated by CEA, CNRS and INRIA at the following URL
+ * "http://www.cecill.info".
+ *
+ * As a counterpart to the access to the source code and rights to copy,
+ * modify and redistribute granted by the license, users are provided only
+ * with a limited warranty and the software's author, the holder of the
+ * economic rights, and the successive licensors have only limited
+ * liability.
+ *
+ * In this respect, the user's attention is drawn to the risks associated
+ * with loading, using, modifying and/or developing or reproducing the
+ * software by the user in light of its specific status of free software,
+ * that may mean that it is complicated to manipulate, and that also
+ * therefore means that it is reserved for developers and experienced
+ * professionals having in-depth computer knowledge. Users are therefore
+ * encouraged to load and test the software's suitability as regards their
+ * requirements in conditions enabling the security of their systems and/or
+ * data to be ensured and, more generally, to use and operate it in the
+ * same conditions as regards security.
+ *
+ * The fact that you are presently reading this means that you have had
+ * knowledge of the CeCILL license and that you accept its terms. */
+
+#ifndef SCHIFF_THUMBNAIL_H
+#define SCHIFF_THUMBNAIL_H
+
+#include <rsys/rsys.h>
+
+struct s3d_scene;
+
+extern LOCAL_SYM void
+schiff_thumbnail
+ (struct s3d_scene* scn,
+ const size_t definition);
+
+#endif /* SCHIFF_THUMBNAIL_H */
+
