2 * Copyright 2011, Blender Foundation.
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11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
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16 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
23 #include "COM_GlareFogGlowOperation.h"
24 #include "MEM_guardedalloc.h"
27 * 2D Fast Hartley Transform, used for convolution
32 // returns next highest power of 2 of x, as well it's log2 in L2
33 static unsigned int nextPow2(unsigned int x, unsigned int *L2)
35 unsigned int pw, x_notpow2 = x & (x - 1);
37 while (x >>= 1) ++(*L2);
39 if (x_notpow2) { (*L2)++; pw <<= 1; }
43 //------------------------------------------------------------------------------
45 // from FXT library by Joerg Arndt, faster in order bitreversal
46 // use: r = revbin_upd(r, h) where h = N>>1
47 static unsigned int revbin_upd(unsigned int r, unsigned int h)
49 while (!((r ^= h) & h)) h >>= 1;
52 //------------------------------------------------------------------------------
53 static void FHT(fREAL *data, unsigned int M, unsigned int inverse)
55 double tt, fc, dc, fs, ds, a = M_PI;
57 int n2, bd, bl, istep, k, len = 1 << M, n = 1;
60 unsigned int Nh = len >> 1;
61 for (i = 1; i < (len - 1); ++i) {
62 j = revbin_upd(j, Nh);
71 fREAL *data_n = &data[n];
74 for (k = 0; k < len; k += istep) {
76 data_n[k] = data[k] - t1;
83 fs = ds = sqrt(1.0 - fc * fc); //sin(a);
85 for (bl = 1; bl < n2; bl++) {
86 fREAL *data_nbd = &data_n[bd];
87 fREAL *data_bd = &data[bd];
88 for (k = bl; k < len; k += istep) {
89 t1 = fc * data_n[k] + fs * data_nbd[k];
90 t2 = fs * data_n[k] - fc * data_nbd[k];
91 data_n[k] = data[k] - t1;
92 data_nbd[k] = data_bd[k] - t2;
96 tt = fc * dc - fs * ds;
97 fs = fs * dc + fc * ds;
104 for (k = n2; k < len; k += istep) {
106 data_n[k] = data[k] - t1;
116 fREAL sc = (fREAL)1 / (fREAL)len;
117 for (k = 0; k < len; ++k)
121 //------------------------------------------------------------------------------
122 /* 2D Fast Hartley Transform, Mx/My -> log2 of width/height,
123 * nzp -> the row where zero pad data starts,
124 * inverse -> see above */
125 static void FHT2D(fREAL *data, unsigned int Mx, unsigned int My,
126 unsigned int nzp, unsigned int inverse)
128 unsigned int i, j, Nx, Ny, maxy;
134 // rows (forward transform skips 0 pad data)
135 maxy = inverse ? Ny : nzp;
136 for (j = 0; j < maxy; ++j)
137 FHT(&data[Nx * j], Mx, inverse);
140 if (Nx == Ny) { // square
141 for (j = 0; j < Ny; ++j)
142 for (i = j + 1; i < Nx; ++i) {
143 unsigned int op = i + (j << Mx), np = j + (i << My);
144 t = data[op], data[op] = data[np], data[np] = t;
147 else { // rectangular
148 unsigned int k, Nym = Ny - 1, stm = 1 << (Mx + My);
149 for (i = 0; stm > 0; i++) {
150 #define PRED(k) (((k & Nym) << Mx) + (k >> My))
151 for (j = PRED(i); j > i; j = PRED(j)) ;
153 for (k = i, j = PRED(i); j != i; k = j, j = PRED(j), stm--) {
154 t = data[j], data[j] = data[k], data[k] = t;
160 // swap Mx/My & Nx/Ny
161 i = Nx, Nx = Ny, Ny = i;
162 i = Mx, Mx = My, My = i;
164 // now columns == transposed rows
165 for (j = 0; j < Ny; ++j)
166 FHT(&data[Nx * j], Mx, inverse);
169 for (j = 0; j <= (Ny >> 1); j++) {
170 unsigned int jm = (Ny - j) & (Ny - 1);
171 unsigned int ji = j << Mx;
172 unsigned int jmi = jm << Mx;
173 for (i = 0; i <= (Nx >> 1); i++) {
174 unsigned int im = (Nx - i) & (Nx - 1);
175 fREAL A = data[ji + i];
176 fREAL B = data[jmi + i];
177 fREAL C = data[ji + im];
178 fREAL D = data[jmi + im];
179 fREAL E = (fREAL)0.5 * ((A + D) - (B + C));
180 data[ji + i] = A - E;
181 data[jmi + i] = B + E;
182 data[ji + im] = C + E;
183 data[jmi + im] = D - E;
189 //------------------------------------------------------------------------------
191 /* 2D convolution calc, d1 *= d2, M/N - > log2 of width/height */
192 static void fht_convolve(fREAL *d1, fREAL *d2, unsigned int M, unsigned int N)
195 unsigned int i, j, k, L, mj, mL;
196 unsigned int m = 1 << M, n = 1 << N;
197 unsigned int m2 = 1 << (M - 1), n2 = 1 << (N - 1);
198 unsigned int mn2 = m << (N - 1);
203 d1[m2 + mn2] *= d2[m2 + mn2];
204 for (i = 1; i < m2; i++) {
206 a = d1[i] * d2[i] - d1[k] * d2[k];
207 b = d1[k] * d2[i] + d1[i] * d2[k];
208 d1[i] = (b + a) * (fREAL)0.5;
209 d1[k] = (b - a) * (fREAL)0.5;
210 a = d1[i + mn2] * d2[i + mn2] - d1[k + mn2] * d2[k + mn2];
211 b = d1[k + mn2] * d2[i + mn2] + d1[i + mn2] * d2[k + mn2];
212 d1[i + mn2] = (b + a) * (fREAL)0.5;
213 d1[k + mn2] = (b - a) * (fREAL)0.5;
215 for (j = 1; j < n2; j++) {
219 a = d1[mj] * d2[mj] - d1[mL] * d2[mL];
220 b = d1[mL] * d2[mj] + d1[mj] * d2[mL];
221 d1[mj] = (b + a) * (fREAL)0.5;
222 d1[mL] = (b - a) * (fREAL)0.5;
223 a = d1[m2 + mj] * d2[m2 + mj] - d1[m2 + mL] * d2[m2 + mL];
224 b = d1[m2 + mL] * d2[m2 + mj] + d1[m2 + mj] * d2[m2 + mL];
225 d1[m2 + mj] = (b + a) * (fREAL)0.5;
226 d1[m2 + mL] = (b - a) * (fREAL)0.5;
228 for (i = 1; i < m2; i++) {
230 for (j = 1; j < n2; j++) {
234 a = d1[i + mj] * d2[i + mj] - d1[k + mL] * d2[k + mL];
235 b = d1[k + mL] * d2[i + mj] + d1[i + mj] * d2[k + mL];
236 d1[i + mj] = (b + a) * (fREAL)0.5;
237 d1[k + mL] = (b - a) * (fREAL)0.5;
238 a = d1[i + mL] * d2[i + mL] - d1[k + mj] * d2[k + mj];
239 b = d1[k + mj] * d2[i + mL] + d1[i + mL] * d2[k + mj];
240 d1[i + mL] = (b + a) * (fREAL)0.5;
241 d1[k + mj] = (b - a) * (fREAL)0.5;
245 //------------------------------------------------------------------------------
247 void convolve(float *dst, MemoryBuffer *in1, MemoryBuffer *in2)
249 fREAL *data1, *data2, *fp;
250 unsigned int w2, h2, hw, hh, log2_w, log2_h;
253 int xbl, ybl, nxb, nyb, xbsz, ybsz;
255 const unsigned int kernelWidth = in2->getWidth();
256 const unsigned int kernelHeight = in2->getHeight();
257 const unsigned int imageWidth = in1->getWidth();
258 const unsigned int imageHeight = in1->getHeight();
259 float *kernelBuffer = in2->getBuffer();
260 float *imageBuffer = in1->getBuffer();
262 MemoryBuffer *rdst = new MemoryBuffer(NULL, in1->getRect());
263 memset(rdst->getBuffer(), 0, rdst->getWidth() * rdst->getHeight() * COM_NUMBER_OF_CHANNELS * sizeof(float));
265 // convolution result width & height
266 w2 = 2 * kernelWidth - 1;
267 h2 = 2 * kernelHeight - 1;
268 // FFT pow2 required size & log2
269 w2 = nextPow2(w2, &log2_w);
270 h2 = nextPow2(h2, &log2_h);
273 data1 = (fREAL *)MEM_callocN(3 * w2 * h2 * sizeof(fREAL), "convolve_fast FHT data1");
274 data2 = (fREAL *)MEM_callocN(w2 * h2 * sizeof(fREAL), "convolve_fast FHT data2");
276 // normalize convolutor
277 wt[0] = wt[1] = wt[2] = 0.f;
278 for (y = 0; y < kernelHeight; y++) {
279 colp = (fRGB *)&kernelBuffer[y * kernelWidth * COM_NUMBER_OF_CHANNELS];
280 for (x = 0; x < kernelWidth; x++)
281 add_v3_v3(wt, colp[x]);
283 if (wt[0] != 0.f) wt[0] = 1.f / wt[0];
284 if (wt[1] != 0.f) wt[1] = 1.f / wt[1];
285 if (wt[2] != 0.f) wt[2] = 1.f / wt[2];
286 for (y = 0; y < kernelHeight; y++) {
287 colp = (fRGB *)&kernelBuffer[y * kernelWidth * COM_NUMBER_OF_CHANNELS];
288 for (x = 0; x < kernelWidth; x++)
289 mul_v3_v3(colp[x], wt);
292 // copy image data, unpacking interleaved RGBA into separate channels
293 // only need to calc data1 once
296 hw = kernelWidth >> 1;
297 hh = kernelHeight >> 1;
298 xbsz = (w2 + 1) - kernelWidth;
299 ybsz = (h2 + 1) - kernelHeight;
300 nxb = imageWidth / xbsz;
301 if (imageWidth % xbsz) nxb++;
302 nyb = imageHeight / ybsz;
303 if (imageHeight % ybsz) nyb++;
304 for (ybl = 0; ybl < nyb; ybl++) {
305 for (xbl = 0; xbl < nxb; xbl++) {
307 // each channel one by one
308 for (ch = 0; ch < 3; ch++) {
309 fREAL *data1ch = &data1[ch * w2 * h2];
311 // only need to calc fht data from in2 once, can re-use for every block
313 // in2, channel ch -> data1
314 for (y = 0; y < kernelHeight; y++) {
315 fp = &data1ch[y * w2];
316 colp = (fRGB *)&kernelBuffer[y * kernelWidth * COM_NUMBER_OF_CHANNELS];
317 for (x = 0; x < kernelWidth; x++)
322 // in1, channel ch -> data2
323 memset(data2, 0, w2 * h2 * sizeof(fREAL));
324 for (y = 0; y < ybsz; y++) {
325 int yy = ybl * ybsz + y;
326 if (yy >= imageHeight) continue;
328 colp = (fRGB *)&imageBuffer[yy * imageWidth * COM_NUMBER_OF_CHANNELS];
329 for (x = 0; x < xbsz; x++) {
330 int xx = xbl * xbsz + x;
331 if (xx >= imageWidth) continue;
332 fp[x] = colp[xx][ch];
337 // zero pad data start is different for each == height+1
338 if (!in2done) FHT2D(data1ch, log2_w, log2_h, kernelHeight + 1, 0);
339 FHT2D(data2, log2_w, log2_h, kernelHeight + 1, 0);
341 // FHT2D transposed data, row/col now swapped
342 // convolve & inverse FHT
343 fht_convolve(data2, data1ch, log2_h, log2_w);
344 FHT2D(data2, log2_h, log2_w, 0, 1);
345 // data again transposed, so in order again
347 // overlap-add result
348 for (y = 0; y < (int)h2; y++) {
349 const int yy = ybl * ybsz + y - hh;
350 if ((yy < 0) || (yy >= imageHeight)) continue;
352 colp = (fRGB *)&rdst->getBuffer()[yy * imageWidth * COM_NUMBER_OF_CHANNELS];
353 for (x = 0; x < (int)w2; x++) {
354 const int xx = xbl * xbsz + x - hw;
355 if ((xx < 0) || (xx >= imageWidth)) continue;
356 colp[xx][ch] += fp[x];
367 memcpy(dst, rdst->getBuffer(), sizeof(float) * imageWidth * imageHeight * COM_NUMBER_OF_CHANNELS);
371 void GlareFogGlowOperation::generateGlare(float *data, MemoryBuffer *inputTile, NodeGlare *settings)
374 float scale, u, v, r, w, d;
377 unsigned int sz = 1 << settings->size;
378 const float cs_r = 1.f, cs_g = 1.f, cs_b = 1.f;
381 // make the convolution kernel
383 BLI_rcti_init(&kernelRect, 0, sz, 0, sz);
384 ckrn = new MemoryBuffer(NULL, &kernelRect);
386 scale = 0.25f * sqrtf((float)(sz * sz));
388 for (y = 0; y < sz; ++y) {
389 v = 2.f * (y / (float)sz) - 1.0f;
390 for (x = 0; x < sz; ++x) {
391 u = 2.f * (x / (float)sz) - 1.0f;
392 r = (u * u + v * v) * scale;
393 d = -sqrtf(sqrtf(sqrtf(r))) * 9.0f;
394 fcol[0] = expf(d * cs_r), fcol[1] = expf(d * cs_g), fcol[2] = expf(d * cs_b);
395 // linear window good enough here, visual result counts, not scientific analysis
396 //w = (1.f-fabs(u))*(1.f-fabs(v));
397 // actually, Hanning window is ok, cos^2 for some reason is slower
398 w = (0.5f + 0.5f * cos((double)u * M_PI)) * (0.5f + 0.5f * cos((double)v * M_PI));
400 ckrn->writePixel(x, y, fcol);
404 convolve(data, inputTile, ckrn);