1 2 /* 3 * Copyright 2006 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #include "SkCamera.h" 11 12 static SkScalar SkScalarDotDiv(int count, const SkScalar a[], int step_a, 13 const SkScalar b[], int step_b, 14 SkScalar denom) { 15 #ifdef SK_SCALAR_IS_FLOAT 16 float prod = 0; 17 for (int i = 0; i < count; i++) { 18 prod += a[0] * b[0]; 19 a += step_a; 20 b += step_b; 21 } 22 return prod / denom; 23 #else 24 Sk64 prod, tmp; 25 26 prod.set(0); 27 for (int i = 0; i < count; i++) { 28 tmp.setMul(a[0], b[0]); 29 prod.add(tmp); 30 a += step_a; 31 b += step_b; 32 } 33 prod.div(denom, Sk64::kRound_DivOption); 34 return prod.get32(); 35 #endif 36 } 37 38 static SkScalar SkScalarDot(int count, const SkScalar a[], int step_a, 39 const SkScalar b[], int step_b) { 40 #ifdef SK_SCALAR_IS_FLOAT 41 float prod = 0; 42 for (int i = 0; i < count; i++) { 43 prod += a[0] * b[0]; 44 a += step_a; 45 b += step_b; 46 } 47 return prod; 48 #else 49 Sk64 prod, tmp; 50 51 prod.set(0); 52 for (int i = 0; i < count; i++) { 53 tmp.setMul(a[0], b[0]); 54 prod.add(tmp); 55 a += step_a; 56 b += step_b; 57 } 58 return prod.getFixed(); 59 #endif 60 } 61 62 /////////////////////////////////////////////////////////////////////////////// 63 64 SkUnitScalar SkPoint3D::normalize(SkUnit3D* unit) const { 65 #ifdef SK_SCALAR_IS_FLOAT 66 float mag = sk_float_sqrt(fX*fX + fY*fY + fZ*fZ); 67 if (mag) { 68 float scale = 1.0f / mag; 69 unit->fX = fX * scale; 70 unit->fY = fY * scale; 71 unit->fZ = fZ * scale; 72 } else { 73 unit->fX = unit->fY = unit->fZ = 0; 74 } 75 #else 76 Sk64 tmp1, tmp2; 77 78 tmp1.setMul(fX, fX); 79 tmp2.setMul(fY, fY); 80 tmp1.add(tmp2); 81 tmp2.setMul(fZ, fZ); 82 tmp1.add(tmp2); 83 84 SkFixed mag = tmp1.getSqrt(); 85 if (mag) { 86 // what if mag < SK_Fixed1 ??? we will underflow the fixdiv 87 SkFixed scale = SkFixedDiv(SK_Fract1, mag); 88 unit->fX = SkFixedMul(fX, scale); 89 unit->fY = SkFixedMul(fY, scale); 90 unit->fZ = SkFixedMul(fZ, scale); 91 } else { 92 unit->fX = unit->fY = unit->fZ = 0; 93 } 94 #endif 95 return mag; 96 } 97 98 SkUnitScalar SkUnit3D::Dot(const SkUnit3D& a, const SkUnit3D& b) { 99 return SkUnitScalarMul(a.fX, b.fX) + 100 SkUnitScalarMul(a.fY, b.fY) + 101 SkUnitScalarMul(a.fZ, b.fZ); 102 } 103 104 void SkUnit3D::Cross(const SkUnit3D& a, const SkUnit3D& b, SkUnit3D* cross) { 105 SkASSERT(cross); 106 107 // use x,y,z, in case &a == cross or &b == cross 108 109 SkScalar x = SkUnitScalarMul(a.fY, b.fZ) - SkUnitScalarMul(a.fZ, b.fY); 110 SkScalar y = SkUnitScalarMul(a.fZ, b.fX) - SkUnitScalarMul(a.fX, b.fY); 111 SkScalar z = SkUnitScalarMul(a.fX, b.fY) - SkUnitScalarMul(a.fY, b.fX); 112 113 cross->set(x, y, z); 114 } 115 116 /////////////////////////////////////////////////////////////////////////////// 117 118 SkPatch3D::SkPatch3D() { 119 this->reset(); 120 } 121 122 void SkPatch3D::reset() { 123 fOrigin.set(0, 0, 0); 124 fU.set(SK_Scalar1, 0, 0); 125 fV.set(0, -SK_Scalar1, 0); 126 } 127 128 void SkPatch3D::transform(const SkMatrix3D& m, SkPatch3D* dst) const { 129 if (dst == NULL) { 130 dst = (SkPatch3D*)this; 131 } 132 m.mapVector(fU, &dst->fU); 133 m.mapVector(fV, &dst->fV); 134 m.mapPoint(fOrigin, &dst->fOrigin); 135 } 136 137 SkScalar SkPatch3D::dotWith(SkScalar dx, SkScalar dy, SkScalar dz) const { 138 SkScalar cx = SkScalarMul(fU.fY, fV.fZ) - SkScalarMul(fU.fZ, fV.fY); 139 SkScalar cy = SkScalarMul(fU.fZ, fV.fX) - SkScalarMul(fU.fX, fV.fY); 140 SkScalar cz = SkScalarMul(fU.fX, fV.fY) - SkScalarMul(fU.fY, fV.fX); 141 142 return SkScalarMul(cx, dx) + SkScalarMul(cy, dy) + SkScalarMul(cz, dz); 143 } 144 145 /////////////////////////////////////////////////////////////////////////////// 146 147 void SkMatrix3D::reset() { 148 memset(fMat, 0, sizeof(fMat)); 149 fMat[0][0] = fMat[1][1] = fMat[2][2] = SK_Scalar1; 150 } 151 152 void SkMatrix3D::setTranslate(SkScalar x, SkScalar y, SkScalar z) { 153 memset(fMat, 0, sizeof(fMat)); 154 fMat[0][0] = x; 155 fMat[1][1] = y; 156 fMat[2][2] = z; 157 } 158 159 void SkMatrix3D::setRotateX(SkScalar degX) { 160 SkScalar s, c; 161 162 s = SkScalarSinCos(SkDegreesToRadians(degX), &c); 163 this->setRow(0, SK_Scalar1, 0, 0); 164 this->setRow(1, 0, c, -s); 165 this->setRow(2, 0, s, c); 166 } 167 168 void SkMatrix3D::setRotateY(SkScalar degY) { 169 SkScalar s, c; 170 171 s = SkScalarSinCos(SkDegreesToRadians(degY), &c); 172 this->setRow(0, c, 0, -s); 173 this->setRow(1, 0, SK_Scalar1, 0); 174 this->setRow(2, s, 0, c); 175 } 176 177 void SkMatrix3D::setRotateZ(SkScalar degZ) { 178 SkScalar s, c; 179 180 s = SkScalarSinCos(SkDegreesToRadians(degZ), &c); 181 this->setRow(0, c, -s, 0); 182 this->setRow(1, s, c, 0); 183 this->setRow(2, 0, 0, SK_Scalar1); 184 } 185 186 void SkMatrix3D::preTranslate(SkScalar x, SkScalar y, SkScalar z) { 187 SkScalar col[3] = { x, y, z}; 188 189 for (int i = 0; i < 3; i++) { 190 fMat[i][3] += SkScalarDot(3, &fMat[i][0], 1, col, 1); 191 } 192 } 193 194 void SkMatrix3D::preRotateX(SkScalar degX) { 195 SkMatrix3D m; 196 m.setRotateX(degX); 197 this->setConcat(*this, m); 198 } 199 200 void SkMatrix3D::preRotateY(SkScalar degY) { 201 SkMatrix3D m; 202 m.setRotateY(degY); 203 this->setConcat(*this, m); 204 } 205 206 void SkMatrix3D::preRotateZ(SkScalar degZ) { 207 SkMatrix3D m; 208 m.setRotateZ(degZ); 209 this->setConcat(*this, m); 210 } 211 212 void SkMatrix3D::setConcat(const SkMatrix3D& a, const SkMatrix3D& b) { 213 SkMatrix3D tmp; 214 SkMatrix3D* c = this; 215 216 if (this == &a || this == &b) { 217 c = &tmp; 218 } 219 for (int i = 0; i < 3; i++) { 220 for (int j = 0; j < 3; j++) { 221 c->fMat[i][j] = SkScalarDot(3, &a.fMat[i][0], 1, &b.fMat[0][j], 4); 222 } 223 c->fMat[i][3] = SkScalarDot(3, &a.fMat[i][0], 1, 224 &b.fMat[0][3], 4) + a.fMat[i][3]; 225 } 226 227 if (c == &tmp) { 228 *this = tmp; 229 } 230 } 231 232 void SkMatrix3D::mapPoint(const SkPoint3D& src, SkPoint3D* dst) const { 233 SkScalar x = SkScalarDot(3, &fMat[0][0], 1, &src.fX, 1) + fMat[0][3]; 234 SkScalar y = SkScalarDot(3, &fMat[1][0], 1, &src.fX, 1) + fMat[1][3]; 235 SkScalar z = SkScalarDot(3, &fMat[2][0], 1, &src.fX, 1) + fMat[2][3]; 236 dst->set(x, y, z); 237 } 238 239 void SkMatrix3D::mapVector(const SkVector3D& src, SkVector3D* dst) const { 240 SkScalar x = SkScalarDot(3, &fMat[0][0], 1, &src.fX, 1); 241 SkScalar y = SkScalarDot(3, &fMat[1][0], 1, &src.fX, 1); 242 SkScalar z = SkScalarDot(3, &fMat[2][0], 1, &src.fX, 1); 243 dst->set(x, y, z); 244 } 245 246 /////////////////////////////////////////////////////////////////////////////// 247 248 SkCamera3D::SkCamera3D() { 249 this->reset(); 250 } 251 252 void SkCamera3D::reset() { 253 fLocation.set(0, 0, -SkIntToScalar(576)); // 8 inches backward 254 fAxis.set(0, 0, SK_Scalar1); // forward 255 fZenith.set(0, -SK_Scalar1, 0); // up 256 257 fObserver.set(0, 0, fLocation.fZ); 258 259 fNeedToUpdate = true; 260 } 261 262 void SkCamera3D::update() { 263 fNeedToUpdate = true; 264 } 265 266 void SkCamera3D::doUpdate() const { 267 SkUnit3D axis, zenith, cross; 268 269 fAxis.normalize(&axis); 270 271 { 272 SkScalar dot = SkUnit3D::Dot(*SkTCast<const SkUnit3D*>(&fZenith), axis); 273 274 zenith.fX = fZenith.fX - SkUnitScalarMul(dot, axis.fX); 275 zenith.fY = fZenith.fY - SkUnitScalarMul(dot, axis.fY); 276 zenith.fZ = fZenith.fZ - SkUnitScalarMul(dot, axis.fZ); 277 278 SkTCast<SkPoint3D*>(&zenith)->normalize(&zenith); 279 } 280 281 SkUnit3D::Cross(axis, zenith, &cross); 282 283 { 284 SkMatrix* orien = &fOrientation; 285 SkScalar x = fObserver.fX; 286 SkScalar y = fObserver.fY; 287 SkScalar z = fObserver.fZ; 288 289 orien->set(SkMatrix::kMScaleX, SkUnitScalarMul(x, axis.fX) - SkUnitScalarMul(z, cross.fX)); 290 orien->set(SkMatrix::kMSkewX, SkUnitScalarMul(x, axis.fY) - SkUnitScalarMul(z, cross.fY)); 291 orien->set(SkMatrix::kMTransX, SkUnitScalarMul(x, axis.fZ) - SkUnitScalarMul(z, cross.fZ)); 292 orien->set(SkMatrix::kMSkewY, SkUnitScalarMul(y, axis.fX) - SkUnitScalarMul(z, zenith.fX)); 293 orien->set(SkMatrix::kMScaleY, SkUnitScalarMul(y, axis.fY) - SkUnitScalarMul(z, zenith.fY)); 294 orien->set(SkMatrix::kMTransY, SkUnitScalarMul(y, axis.fZ) - SkUnitScalarMul(z, zenith.fZ)); 295 orien->set(SkMatrix::kMPersp0, axis.fX); 296 orien->set(SkMatrix::kMPersp1, axis.fY); 297 orien->set(SkMatrix::kMPersp2, axis.fZ); 298 } 299 } 300 301 void SkCamera3D::patchToMatrix(const SkPatch3D& quilt, SkMatrix* matrix) const { 302 if (fNeedToUpdate) { 303 this->doUpdate(); 304 fNeedToUpdate = false; 305 } 306 307 const SkScalar* mapPtr = (const SkScalar*)(const void*)&fOrientation; 308 const SkScalar* patchPtr; 309 SkPoint3D diff; 310 SkScalar dot; 311 312 diff.fX = quilt.fOrigin.fX - fLocation.fX; 313 diff.fY = quilt.fOrigin.fY - fLocation.fY; 314 diff.fZ = quilt.fOrigin.fZ - fLocation.fZ; 315 316 dot = SkUnit3D::Dot(*SkTCast<const SkUnit3D*>(&diff), 317 *SkTCast<const SkUnit3D*>(SkTCast<const SkScalar*>(&fOrientation) + 6)); 318 319 patchPtr = (const SkScalar*)&quilt; 320 matrix->set(SkMatrix::kMScaleX, SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot)); 321 matrix->set(SkMatrix::kMSkewY, SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot)); 322 matrix->set(SkMatrix::kMPersp0, SkScalarDotDiv(3, patchPtr, 1, mapPtr+6, 1, dot)); 323 324 patchPtr += 3; 325 matrix->set(SkMatrix::kMSkewX, SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot)); 326 matrix->set(SkMatrix::kMScaleY, SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot)); 327 matrix->set(SkMatrix::kMPersp1, SkScalarDotDiv(3, patchPtr, 1, mapPtr+6, 1, dot)); 328 329 patchPtr = (const SkScalar*)(const void*)&diff; 330 matrix->set(SkMatrix::kMTransX, SkScalarDotDiv(3, patchPtr, 1, mapPtr, 1, dot)); 331 matrix->set(SkMatrix::kMTransY, SkScalarDotDiv(3, patchPtr, 1, mapPtr+3, 1, dot)); 332 matrix->set(SkMatrix::kMPersp2, SK_UnitScalar1); 333 } 334 335 /////////////////////////////////////////////////////////////////////////////// 336 337 Sk3DView::Sk3DView() { 338 fInitialRec.fMatrix.reset(); 339 fRec = &fInitialRec; 340 } 341 342 Sk3DView::~Sk3DView() { 343 Rec* rec = fRec; 344 while (rec != &fInitialRec) { 345 Rec* next = rec->fNext; 346 SkDELETE(rec); 347 rec = next; 348 } 349 } 350 351 void Sk3DView::save() { 352 Rec* rec = SkNEW(Rec); 353 rec->fNext = fRec; 354 rec->fMatrix = fRec->fMatrix; 355 fRec = rec; 356 } 357 358 void Sk3DView::restore() { 359 SkASSERT(fRec != &fInitialRec); 360 Rec* next = fRec->fNext; 361 SkDELETE(fRec); 362 fRec = next; 363 } 364 365 #ifdef SK_BUILD_FOR_ANDROID 366 void Sk3DView::setCameraLocation(SkScalar x, SkScalar y, SkScalar z) { 367 // the camera location is passed in inches, set in pt 368 SkScalar lz = z * SkFloatToScalar(72.0f); 369 fCamera.fLocation.set(x * SkFloatToScalar(72.0f), y * SkFloatToScalar(72.0f), lz); 370 fCamera.fObserver.set(0, 0, lz); 371 fCamera.update(); 372 373 } 374 375 SkScalar Sk3DView::getCameraLocationX() { 376 return fCamera.fLocation.fX / SkFloatToScalar(72.0f); 377 } 378 379 SkScalar Sk3DView::getCameraLocationY() { 380 return fCamera.fLocation.fY / SkFloatToScalar(72.0f); 381 } 382 383 SkScalar Sk3DView::getCameraLocationZ() { 384 return fCamera.fLocation.fZ / SkFloatToScalar(72.0f); 385 } 386 #endif 387 388 void Sk3DView::translate(SkScalar x, SkScalar y, SkScalar z) { 389 fRec->fMatrix.preTranslate(x, y, z); 390 } 391 392 void Sk3DView::rotateX(SkScalar deg) { 393 fRec->fMatrix.preRotateX(deg); 394 } 395 396 void Sk3DView::rotateY(SkScalar deg) { 397 fRec->fMatrix.preRotateY(deg); 398 } 399 400 void Sk3DView::rotateZ(SkScalar deg) { 401 fRec->fMatrix.preRotateZ(deg); 402 } 403 404 SkScalar Sk3DView::dotWithNormal(SkScalar x, SkScalar y, SkScalar z) const { 405 SkPatch3D patch; 406 patch.transform(fRec->fMatrix); 407 return patch.dotWith(x, y, z); 408 } 409 410 void Sk3DView::getMatrix(SkMatrix* matrix) const { 411 if (matrix != NULL) { 412 SkPatch3D patch; 413 patch.transform(fRec->fMatrix); 414 fCamera.patchToMatrix(patch, matrix); 415 } 416 } 417 418 #include "SkCanvas.h" 419 420 void Sk3DView::applyToCanvas(SkCanvas* canvas) const { 421 SkMatrix matrix; 422 423 this->getMatrix(&matrix); 424 canvas->concat(matrix); 425 } 426