diff options
| -rw-r--r-- | math.h | 26 | ||||
| -rw-r--r-- | rect.c | 63 |
2 files changed, 52 insertions, 37 deletions
@@ -27,6 +27,7 @@ #define REPLACE_WITH_AMDLIBM #include <amdlibm.h> #undef nearbyint +#undef floor #endif #define clamp(a,min,max) (a > max ? max : (a < min ? min : a)) @@ -55,6 +56,14 @@ inline void translate (const double2 xy, double2 matrix[3]) { matrix[2] = xy; } +/* Create affine scaling matrix + */ +inline void scale (const double2 xy, double2 matrix[3]) { + matrix[0] = (double2) { xy[0], 0.0 }; + matrix[1] = (double2) { 0.0, xy[1] }; + matrix[2] = (double2) { 0.0, 0.0 }; +} + /* Multiply two affine matrices a, b and store the result in c. * * The last row of each matrix is assumed to be 0, 0, 1. @@ -65,6 +74,23 @@ inline void matrixmul (const double2 a[3], const double2 b[3], double2 c[3]) { c[2] = a[0] * b[2][0] + a[1] * b[2][1] + a[2]; } +/* Affine matrix that transforms rect from (x1, y1, x2, y2) into rect to + */ +inline void translate_rect (const double4 from, const double4 to, + double2 matrix[3]) { + const double2 from_edge = (double2) { from[0], from[1] }, + to_edge = (double2) { to[0], to[1] }; + /* first align one of A and B’s edges */ + double2 translate_edge[3]; + translate (to_edge - from_edge, translate_edge); + /* then scale it up or down */ + double2 scale_rect[3]; + scale ((double2) { (to[2] - to[0])/(from[2] - from[0]), + (to[3] - to[1])/(from[3] - from[1])}, scale_rect); + /* the result is scale*translate (i.e. translate first) */ + matrixmul (scale_rect, translate_edge, matrix); +} + /* Create rotation around center. Note that matrix multiplication is * right-associative, thus A*B*C == A*(B*C) */ inline void rotate_center (const double2 center, const double angle, double2 out[3]) { @@ -29,12 +29,7 @@ typedef struct { double timelimit; unsigned int sub_batch_size, fuse; unsigned short *xform_distrib; - - /* camera stuff */ - double ws0, wb0s0, hs1, hb1s1; /* shortcuts for indexing */ - double bounds[4]; /* Corner coords of viewable area */ - double2 rot[3]; /* Rotation transformation */ - double ppux, ppuy; + double2 camera[3]; } render_constants; /* Lookup color [0,1] @@ -112,20 +107,18 @@ static void iter_thread (flam3_genome * const input_genome, /* Put them in the bucket accumulator */ for (unsigned int j = 0; j < c->sub_batch_size; j++) { - double4 p = iter_storage[j]; + const double4 p = iter_storage[j]; - if (genome.rotate != 0.0) { - const double2 p01 = (double2) { p[0], p[1] }; - const double2 rotatedp = apply_affine (p01, c->rot); - p[0] = rotatedp[0]; - p[1] = rotatedp[1]; - } + const double2 origpos = (double2) { p[0], p[1] }; + const double2 transpos = apply_affine (origpos, c->camera); + const unsigned int x = floor (transpos[0]); + const unsigned int y = floor (transpos[1]); /* Skip if out of bounding box or invisible */ - if (p[0] >= c->bounds[0] && p[1] >= c->bounds[1] && - p[0] <= c->bounds[2] && p[1] <= c->bounds[3] && + if (x >= 0 && x < bucket->dim[0] && + y >= 0 && y < bucket->dim[1] && p[3] > 0) { - const size_t ix = (int)(c->ws0 * p[0] - c->wb0s0) + bucket->dim[0] * (int)(c->hs1 * p[1] - c->hb1s1); + const size_t ix = x + bucket->dim[0] * y; #if HAVE_BUILTIN_PREFETCH /* prefetch for reading (0) with no locality (0). This (partially) * hides the load latency for the += operation at the end of this @@ -137,9 +130,7 @@ static void iter_thread (flam3_genome * const input_genome, genome.palette_mode, &input_genome->palette); const double logvis = p[3]; - if (logvis != 1.0) { - interpcolor *= logvis; - } + interpcolor *= logvis; bucket->data[ix] += interpcolor; } @@ -264,27 +255,25 @@ static void compute_camera (const flam3_genome * const genome, assert (bucket != NULL); assert (c != NULL); - double corner0, corner1; - const double scale = pow(2.0, genome->zoom); - c->ppux = genome->pixels_per_unit * scale; - c->ppuy = c->ppux; - //ppux /= spec->pixel_aspect_ratio; - corner0 = genome->center[0] - bucket->dim[0] / c->ppux / 2.0; - corner1 = genome->center[1] - bucket->dim[1] / c->ppuy / 2.0; - c->bounds[0] = corner0; - c->bounds[1] = corner1; - c->bounds[2] = corner0 + bucket->dim[0] / c->ppux; - c->bounds[3] = corner1 + bucket->dim[1] / c->ppuy; - const double size[2] = {1.0 / (c->bounds[2] - c->bounds[0]), - 1.0 / (c->bounds[3] - c->bounds[1])}; + const double ppux = genome->pixels_per_unit * scale; + const double ppuy = ppux; + const double corner0 = genome->center[0] - bucket->dim[0] / ppux / 2.0; + const double corner1 = genome->center[1] - bucket->dim[1] / ppuy / 2.0; + + double2 rot_matrix[3]; rotate_center ((double2) { genome->rot_center[0], genome->rot_center[1] }, - genome->rotate, c->rot); - c->ws0 = bucket->dim[0] * size[0]; - c->wb0s0 = c->ws0 * c->bounds[0]; - c->hs1 = bucket->dim[1] * size[1]; - c->hb1s1 = c->hs1 * c->bounds[1]; + genome->rotate, rot_matrix); + + const double4 from_rect = (double4) { corner0, corner1, + corner0 + bucket->dim[0] / ppux, + corner1 + bucket->dim[1] / ppuy }; + const double4 to_rect = (double4) { 0, 0, bucket->dim[0], bucket->dim[1] }; + double2 transform_matrix[3]; + translate_rect (from_rect, to_rect, transform_matrix); + + matrixmul (transform_matrix, rot_matrix, c->camera); } bool render_bucket (flam3_genome * const genome, bucket * const bucket, |