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
SkScalarDotDiv(int count,const SkScalar a[],int step_a,const SkScalar b[],int step_b,SkScalar denom)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
SkScalarDot(int count,const SkScalar a[],int step_a,const SkScalar b[],int step_b)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
normalize(SkUnit3D * unit) const64 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
Dot(const SkUnit3D & a,const SkUnit3D & b)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
Cross(const SkUnit3D & a,const SkUnit3D & b,SkUnit3D * cross)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
SkPatch3D()118 SkPatch3D::SkPatch3D() {
119 this->reset();
120 }
121
reset()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
transform(const SkMatrix3D & m,SkPatch3D * dst) const128 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
dotWith(SkScalar dx,SkScalar dy,SkScalar dz) const137 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
reset()147 void SkMatrix3D::reset() {
148 memset(fMat, 0, sizeof(fMat));
149 fMat[0][0] = fMat[1][1] = fMat[2][2] = SK_Scalar1;
150 }
151
setTranslate(SkScalar x,SkScalar y,SkScalar z)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
setRotateX(SkScalar degX)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
setRotateY(SkScalar degY)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
setRotateZ(SkScalar degZ)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
preTranslate(SkScalar x,SkScalar y,SkScalar z)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
preRotateX(SkScalar degX)194 void SkMatrix3D::preRotateX(SkScalar degX) {
195 SkMatrix3D m;
196 m.setRotateX(degX);
197 this->setConcat(*this, m);
198 }
199
preRotateY(SkScalar degY)200 void SkMatrix3D::preRotateY(SkScalar degY) {
201 SkMatrix3D m;
202 m.setRotateY(degY);
203 this->setConcat(*this, m);
204 }
205
preRotateZ(SkScalar degZ)206 void SkMatrix3D::preRotateZ(SkScalar degZ) {
207 SkMatrix3D m;
208 m.setRotateZ(degZ);
209 this->setConcat(*this, m);
210 }
211
setConcat(const SkMatrix3D & a,const SkMatrix3D & b)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
mapPoint(const SkPoint3D & src,SkPoint3D * dst) const232 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
mapVector(const SkVector3D & src,SkVector3D * dst) const239 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
SkCamera3D()248 SkCamera3D::SkCamera3D() {
249 this->reset();
250 }
251
reset()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
update()262 void SkCamera3D::update() {
263 fNeedToUpdate = true;
264 }
265
doUpdate() const266 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
patchToMatrix(const SkPatch3D & quilt,SkMatrix * matrix) const301 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
Sk3DView()337 Sk3DView::Sk3DView() {
338 fInitialRec.fMatrix.reset();
339 fRec = &fInitialRec;
340 }
341
~Sk3DView()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
save()351 void Sk3DView::save() {
352 Rec* rec = SkNEW(Rec);
353 rec->fNext = fRec;
354 rec->fMatrix = fRec->fMatrix;
355 fRec = rec;
356 }
357
restore()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
setCameraLocation(SkScalar x,SkScalar y,SkScalar z)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 * 72.0f;
369 fCamera.fLocation.set(x * 72.0f, y * 72.0f, lz);
370 fCamera.fObserver.set(0, 0, lz);
371 fCamera.update();
372
373 }
374
getCameraLocationX()375 SkScalar Sk3DView::getCameraLocationX() {
376 return fCamera.fLocation.fX / 72.0f;
377 }
378
getCameraLocationY()379 SkScalar Sk3DView::getCameraLocationY() {
380 return fCamera.fLocation.fY / 72.0f;
381 }
382
getCameraLocationZ()383 SkScalar Sk3DView::getCameraLocationZ() {
384 return fCamera.fLocation.fZ / 72.0f;
385 }
386 #endif
387
translate(SkScalar x,SkScalar y,SkScalar z)388 void Sk3DView::translate(SkScalar x, SkScalar y, SkScalar z) {
389 fRec->fMatrix.preTranslate(x, y, z);
390 }
391
rotateX(SkScalar deg)392 void Sk3DView::rotateX(SkScalar deg) {
393 fRec->fMatrix.preRotateX(deg);
394 }
395
rotateY(SkScalar deg)396 void Sk3DView::rotateY(SkScalar deg) {
397 fRec->fMatrix.preRotateY(deg);
398 }
399
rotateZ(SkScalar deg)400 void Sk3DView::rotateZ(SkScalar deg) {
401 fRec->fMatrix.preRotateZ(deg);
402 }
403
dotWithNormal(SkScalar x,SkScalar y,SkScalar z) const404 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
getMatrix(SkMatrix * matrix) const410 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
applyToCanvas(SkCanvas * canvas) const420 void Sk3DView::applyToCanvas(SkCanvas* canvas) const {
421 SkMatrix matrix;
422
423 this->getMatrix(&matrix);
424 canvas->concat(matrix);
425 }
426