1 // Copyright 2019 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #include "core/fpdfapi/render/cpdf_rendershading.h"
8
9 #include <algorithm>
10 #include <array>
11 #include <cmath>
12 #include <memory>
13 #include <utility>
14 #include <vector>
15
16 #include "core/fpdfapi/page/cpdf_colorspace.h"
17 #include "core/fpdfapi/page/cpdf_dib.h"
18 #include "core/fpdfapi/page/cpdf_function.h"
19 #include "core/fpdfapi/page/cpdf_meshstream.h"
20 #include "core/fpdfapi/parser/cpdf_array.h"
21 #include "core/fpdfapi/parser/cpdf_dictionary.h"
22 #include "core/fpdfapi/parser/cpdf_stream.h"
23 #include "core/fpdfapi/parser/fpdf_parser_utility.h"
24 #include "core/fpdfapi/render/cpdf_devicebuffer.h"
25 #include "core/fpdfapi/render/cpdf_renderoptions.h"
26 #include "core/fxcrt/fx_safe_types.h"
27 #include "core/fxcrt/fx_system.h"
28 #include "core/fxge/cfx_defaultrenderdevice.h"
29 #include "core/fxge/dib/cfx_dibitmap.h"
30 #include "core/fxge/fx_dib.h"
31
32 namespace {
33
34 constexpr int kShadingSteps = 256;
35
CountOutputsFromFunctions(const std::vector<std::unique_ptr<CPDF_Function>> & funcs)36 uint32_t CountOutputsFromFunctions(
37 const std::vector<std::unique_ptr<CPDF_Function>>& funcs) {
38 FX_SAFE_UINT32 total = 0;
39 for (const auto& func : funcs) {
40 if (func)
41 total += func->CountOutputs();
42 }
43 return total.ValueOrDefault(0);
44 }
45
GetValidatedOutputsCount(const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS)46 uint32_t GetValidatedOutputsCount(
47 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
48 const RetainPtr<CPDF_ColorSpace>& pCS) {
49 uint32_t funcs_outputs = CountOutputsFromFunctions(funcs);
50 return funcs_outputs ? std::max(funcs_outputs, pCS->CountComponents()) : 0;
51 }
52
GetShadingSteps(float t_min,float t_max,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha,size_t results_count)53 std::array<FX_ARGB, kShadingSteps> GetShadingSteps(
54 float t_min,
55 float t_max,
56 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
57 const RetainPtr<CPDF_ColorSpace>& pCS,
58 int alpha,
59 size_t results_count) {
60 ASSERT(results_count >= CountOutputsFromFunctions(funcs));
61 ASSERT(results_count >= pCS->CountComponents());
62 std::array<FX_ARGB, kShadingSteps> shading_steps;
63 std::vector<float> result_array(results_count);
64 float diff = t_max - t_min;
65 for (int i = 0; i < kShadingSteps; ++i) {
66 float input = diff * i / kShadingSteps + t_min;
67 int offset = 0;
68 for (const auto& func : funcs) {
69 if (func) {
70 int nresults = 0;
71 if (func->Call(&input, 1, &result_array[offset], &nresults))
72 offset += nresults;
73 }
74 }
75 float R = 0.0f;
76 float G = 0.0f;
77 float B = 0.0f;
78 pCS->GetRGB(result_array.data(), &R, &G, &B);
79 shading_steps[i] =
80 FXARGB_TODIB(ArgbEncode(alpha, FXSYS_roundf(R * 255),
81 FXSYS_roundf(G * 255), FXSYS_roundf(B * 255)));
82 }
83 return shading_steps;
84 }
85
DrawAxialShading(const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Dictionary * pDict,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha)86 void DrawAxialShading(const RetainPtr<CFX_DIBitmap>& pBitmap,
87 const CFX_Matrix& mtObject2Bitmap,
88 const CPDF_Dictionary* pDict,
89 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
90 const RetainPtr<CPDF_ColorSpace>& pCS,
91 int alpha) {
92 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
93
94 const uint32_t total_results = GetValidatedOutputsCount(funcs, pCS);
95 if (total_results == 0)
96 return;
97
98 const CPDF_Array* pCoords = pDict->GetArrayFor("Coords");
99 if (!pCoords)
100 return;
101
102 float start_x = pCoords->GetNumberAt(0);
103 float start_y = pCoords->GetNumberAt(1);
104 float end_x = pCoords->GetNumberAt(2);
105 float end_y = pCoords->GetNumberAt(3);
106 float t_min = 0;
107 float t_max = 1.0f;
108 const CPDF_Array* pArray = pDict->GetArrayFor("Domain");
109 if (pArray) {
110 t_min = pArray->GetNumberAt(0);
111 t_max = pArray->GetNumberAt(1);
112 }
113 pArray = pDict->GetArrayFor("Extend");
114 const bool bStartExtend = pArray && pArray->GetBooleanAt(0, false);
115 const bool bEndExtend = pArray && pArray->GetBooleanAt(1, false);
116
117 int width = pBitmap->GetWidth();
118 int height = pBitmap->GetHeight();
119 float x_span = end_x - start_x;
120 float y_span = end_y - start_y;
121 float axis_len_square = (x_span * x_span) + (y_span * y_span);
122
123 std::array<FX_ARGB, kShadingSteps> shading_steps =
124 GetShadingSteps(t_min, t_max, funcs, pCS, alpha, total_results);
125
126 int pitch = pBitmap->GetPitch();
127 CFX_Matrix matrix = mtObject2Bitmap.GetInverse();
128 for (int row = 0; row < height; row++) {
129 uint32_t* dib_buf =
130 reinterpret_cast<uint32_t*>(pBitmap->GetBuffer() + row * pitch);
131 for (int column = 0; column < width; column++) {
132 CFX_PointF pos = matrix.Transform(
133 CFX_PointF(static_cast<float>(column), static_cast<float>(row)));
134 float scale =
135 (((pos.x - start_x) * x_span) + ((pos.y - start_y) * y_span)) /
136 axis_len_square;
137 int index = (int32_t)(scale * (kShadingSteps - 1));
138 if (index < 0) {
139 if (!bStartExtend)
140 continue;
141
142 index = 0;
143 } else if (index >= kShadingSteps) {
144 if (!bEndExtend)
145 continue;
146
147 index = kShadingSteps - 1;
148 }
149 dib_buf[column] = shading_steps[index];
150 }
151 }
152 }
153
DrawRadialShading(const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Dictionary * pDict,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha)154 void DrawRadialShading(const RetainPtr<CFX_DIBitmap>& pBitmap,
155 const CFX_Matrix& mtObject2Bitmap,
156 const CPDF_Dictionary* pDict,
157 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
158 const RetainPtr<CPDF_ColorSpace>& pCS,
159 int alpha) {
160 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
161
162 const uint32_t total_results = GetValidatedOutputsCount(funcs, pCS);
163 if (total_results == 0)
164 return;
165
166 const CPDF_Array* pCoords = pDict->GetArrayFor("Coords");
167 if (!pCoords)
168 return;
169
170 float start_x = pCoords->GetNumberAt(0);
171 float start_y = pCoords->GetNumberAt(1);
172 float start_r = pCoords->GetNumberAt(2);
173 float end_x = pCoords->GetNumberAt(3);
174 float end_y = pCoords->GetNumberAt(4);
175 float end_r = pCoords->GetNumberAt(5);
176 float t_min = 0;
177 float t_max = 1.0f;
178 const CPDF_Array* pArray = pDict->GetArrayFor("Domain");
179 if (pArray) {
180 t_min = pArray->GetNumberAt(0);
181 t_max = pArray->GetNumberAt(1);
182 }
183 pArray = pDict->GetArrayFor("Extend");
184 const bool bStartExtend = pArray && pArray->GetBooleanAt(0, false);
185 const bool bEndExtend = pArray && pArray->GetBooleanAt(1, false);
186
187 std::array<FX_ARGB, kShadingSteps> shading_steps =
188 GetShadingSteps(t_min, t_max, funcs, pCS, alpha, total_results);
189
190 const float dx = end_x - start_x;
191 const float dy = end_y - start_y;
192 const float dr = end_r - start_r;
193 const float a = dx * dx + dy * dy - dr * dr;
194 const bool a_is_float_zero = IsFloatZero(a);
195
196 int width = pBitmap->GetWidth();
197 int height = pBitmap->GetHeight();
198 int pitch = pBitmap->GetPitch();
199
200 bool bDecreasing =
201 (dr < 0 && static_cast<int>(sqrt(dx * dx + dy * dy)) < -dr);
202
203 CFX_Matrix matrix = mtObject2Bitmap.GetInverse();
204 for (int row = 0; row < height; row++) {
205 uint32_t* dib_buf =
206 reinterpret_cast<uint32_t*>(pBitmap->GetBuffer() + row * pitch);
207 for (int column = 0; column < width; column++) {
208 CFX_PointF pos = matrix.Transform(
209 CFX_PointF(static_cast<float>(column), static_cast<float>(row)));
210 float pos_dx = pos.x - start_x;
211 float pos_dy = pos.y - start_y;
212 float b = -2 * (pos_dx * dx + pos_dy * dy + start_r * dr);
213 float c = pos_dx * pos_dx + pos_dy * pos_dy - start_r * start_r;
214 float s;
215 if (IsFloatZero(b)) {
216 s = sqrt(-c / a);
217 } else if (a_is_float_zero) {
218 s = -c / b;
219 } else {
220 float b2_4ac = (b * b) - 4 * (a * c);
221 if (b2_4ac < 0)
222 continue;
223
224 float root = sqrt(b2_4ac);
225 float s1 = (-b - root) / (2 * a);
226 float s2 = (-b + root) / (2 * a);
227 if (a <= 0)
228 std::swap(s1, s2);
229 if (bDecreasing)
230 s = (s1 >= 0 || bStartExtend) ? s1 : s2;
231 else
232 s = (s2 <= 1.0f || bEndExtend) ? s2 : s1;
233
234 if (start_r + s * dr < 0)
235 continue;
236 }
237
238 int index = static_cast<int32_t>(s * (kShadingSteps - 1));
239 if (index < 0) {
240 if (!bStartExtend)
241 continue;
242 index = 0;
243 } else if (index >= kShadingSteps) {
244 if (!bEndExtend)
245 continue;
246 index = kShadingSteps - 1;
247 }
248 dib_buf[column] = shading_steps[index];
249 }
250 }
251 }
252
DrawFuncShading(const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Dictionary * pDict,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha)253 void DrawFuncShading(const RetainPtr<CFX_DIBitmap>& pBitmap,
254 const CFX_Matrix& mtObject2Bitmap,
255 const CPDF_Dictionary* pDict,
256 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
257 const RetainPtr<CPDF_ColorSpace>& pCS,
258 int alpha) {
259 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
260
261 const uint32_t total_results = GetValidatedOutputsCount(funcs, pCS);
262 if (total_results == 0)
263 return;
264
265 const CPDF_Array* pDomain = pDict->GetArrayFor("Domain");
266 float xmin = 0.0f;
267 float ymin = 0.0f;
268 float xmax = 1.0f;
269 float ymax = 1.0f;
270 if (pDomain) {
271 xmin = pDomain->GetNumberAt(0);
272 xmax = pDomain->GetNumberAt(1);
273 ymin = pDomain->GetNumberAt(2);
274 ymax = pDomain->GetNumberAt(3);
275 }
276 CFX_Matrix mtDomain2Target = pDict->GetMatrixFor("Matrix");
277 CFX_Matrix matrix =
278 mtObject2Bitmap.GetInverse() * mtDomain2Target.GetInverse();
279 int width = pBitmap->GetWidth();
280 int height = pBitmap->GetHeight();
281 int pitch = pBitmap->GetPitch();
282
283 ASSERT(total_results >= CountOutputsFromFunctions(funcs));
284 ASSERT(total_results >= pCS->CountComponents());
285 std::vector<float> result_array(total_results);
286 for (int row = 0; row < height; ++row) {
287 uint32_t* dib_buf = (uint32_t*)(pBitmap->GetBuffer() + row * pitch);
288 for (int column = 0; column < width; column++) {
289 CFX_PointF pos = matrix.Transform(
290 CFX_PointF(static_cast<float>(column), static_cast<float>(row)));
291 if (pos.x < xmin || pos.x > xmax || pos.y < ymin || pos.y > ymax)
292 continue;
293
294 float input[] = {pos.x, pos.y};
295 int offset = 0;
296 for (const auto& func : funcs) {
297 if (func) {
298 int nresults;
299 if (func->Call(input, 2, &result_array[offset], &nresults))
300 offset += nresults;
301 }
302 }
303
304 float R = 0.0f;
305 float G = 0.0f;
306 float B = 0.0f;
307 pCS->GetRGB(result_array.data(), &R, &G, &B);
308 dib_buf[column] = FXARGB_TODIB(ArgbEncode(
309 alpha, (int32_t)(R * 255), (int32_t)(G * 255), (int32_t)(B * 255)));
310 }
311 }
312 }
313
GetScanlineIntersect(int y,const CFX_PointF & first,const CFX_PointF & second,float * x)314 bool GetScanlineIntersect(int y,
315 const CFX_PointF& first,
316 const CFX_PointF& second,
317 float* x) {
318 if (first.y == second.y)
319 return false;
320
321 if (first.y < second.y) {
322 if (y < first.y || y > second.y)
323 return false;
324 } else if (y < second.y || y > first.y) {
325 return false;
326 }
327 *x = first.x + ((second.x - first.x) * (y - first.y) / (second.y - first.y));
328 return true;
329 }
330
DrawGouraud(const RetainPtr<CFX_DIBitmap> & pBitmap,int alpha,CPDF_MeshVertex triangle[3])331 void DrawGouraud(const RetainPtr<CFX_DIBitmap>& pBitmap,
332 int alpha,
333 CPDF_MeshVertex triangle[3]) {
334 float min_y = triangle[0].position.y;
335 float max_y = triangle[0].position.y;
336 for (int i = 1; i < 3; i++) {
337 min_y = std::min(min_y, triangle[i].position.y);
338 max_y = std::max(max_y, triangle[i].position.y);
339 }
340 if (min_y == max_y)
341 return;
342
343 int min_yi = std::max(static_cast<int>(floor(min_y)), 0);
344 int max_yi = static_cast<int>(ceil(max_y));
345
346 if (max_yi >= pBitmap->GetHeight())
347 max_yi = pBitmap->GetHeight() - 1;
348
349 for (int y = min_yi; y <= max_yi; y++) {
350 int nIntersects = 0;
351 float inter_x[3];
352 float r[3];
353 float g[3];
354 float b[3];
355 for (int i = 0; i < 3; i++) {
356 CPDF_MeshVertex& vertex1 = triangle[i];
357 CPDF_MeshVertex& vertex2 = triangle[(i + 1) % 3];
358 CFX_PointF& position1 = vertex1.position;
359 CFX_PointF& position2 = vertex2.position;
360 bool bIntersect =
361 GetScanlineIntersect(y, position1, position2, &inter_x[nIntersects]);
362 if (!bIntersect)
363 continue;
364
365 float y_dist = (y - position1.y) / (position2.y - position1.y);
366 r[nIntersects] = vertex1.r + ((vertex2.r - vertex1.r) * y_dist);
367 g[nIntersects] = vertex1.g + ((vertex2.g - vertex1.g) * y_dist);
368 b[nIntersects] = vertex1.b + ((vertex2.b - vertex1.b) * y_dist);
369 nIntersects++;
370 }
371 if (nIntersects != 2)
372 continue;
373
374 int min_x, max_x, start_index, end_index;
375 if (inter_x[0] < inter_x[1]) {
376 min_x = (int)floor(inter_x[0]);
377 max_x = (int)ceil(inter_x[1]);
378 start_index = 0;
379 end_index = 1;
380 } else {
381 min_x = (int)floor(inter_x[1]);
382 max_x = (int)ceil(inter_x[0]);
383 start_index = 1;
384 end_index = 0;
385 }
386
387 int start_x = std::max(min_x, 0);
388 int end_x = max_x;
389 if (end_x > pBitmap->GetWidth())
390 end_x = pBitmap->GetWidth();
391
392 uint8_t* dib_buf =
393 pBitmap->GetBuffer() + y * pBitmap->GetPitch() + start_x * 4;
394 float r_unit = (r[end_index] - r[start_index]) / (max_x - min_x);
395 float g_unit = (g[end_index] - g[start_index]) / (max_x - min_x);
396 float b_unit = (b[end_index] - b[start_index]) / (max_x - min_x);
397 float R = r[start_index] + (start_x - min_x) * r_unit;
398 float G = g[start_index] + (start_x - min_x) * g_unit;
399 float B = b[start_index] + (start_x - min_x) * b_unit;
400 for (int x = start_x; x < end_x; x++) {
401 R += r_unit;
402 G += g_unit;
403 B += b_unit;
404 FXARGB_SETDIB(dib_buf,
405 ArgbEncode(alpha, (int32_t)(R * 255), (int32_t)(G * 255),
406 (int32_t)(B * 255)));
407 dib_buf += 4;
408 }
409 }
410 }
411
DrawFreeGouraudShading(const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Stream * pShadingStream,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha)412 void DrawFreeGouraudShading(
413 const RetainPtr<CFX_DIBitmap>& pBitmap,
414 const CFX_Matrix& mtObject2Bitmap,
415 const CPDF_Stream* pShadingStream,
416 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
417 const RetainPtr<CPDF_ColorSpace>& pCS,
418 int alpha) {
419 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
420
421 CPDF_MeshStream stream(kFreeFormGouraudTriangleMeshShading, funcs,
422 pShadingStream, pCS);
423 if (!stream.Load())
424 return;
425
426 CPDF_MeshVertex triangle[3];
427 memset(triangle, 0, sizeof(triangle));
428
429 while (!stream.BitStream()->IsEOF()) {
430 CPDF_MeshVertex vertex;
431 uint32_t flag;
432 if (!stream.ReadVertex(mtObject2Bitmap, &vertex, &flag))
433 return;
434
435 if (flag == 0) {
436 triangle[0] = vertex;
437 for (int j = 1; j < 3; j++) {
438 uint32_t tflag;
439 if (!stream.ReadVertex(mtObject2Bitmap, &triangle[j], &tflag))
440 return;
441 }
442 } else {
443 if (flag == 1)
444 triangle[0] = triangle[1];
445
446 triangle[1] = triangle[2];
447 triangle[2] = vertex;
448 }
449 DrawGouraud(pBitmap, alpha, triangle);
450 }
451 }
452
DrawLatticeGouraudShading(const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Stream * pShadingStream,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,int alpha)453 void DrawLatticeGouraudShading(
454 const RetainPtr<CFX_DIBitmap>& pBitmap,
455 const CFX_Matrix& mtObject2Bitmap,
456 const CPDF_Stream* pShadingStream,
457 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
458 const RetainPtr<CPDF_ColorSpace>& pCS,
459 int alpha) {
460 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
461
462 int row_verts = pShadingStream->GetDict()->GetIntegerFor("VerticesPerRow");
463 if (row_verts < 2)
464 return;
465
466 CPDF_MeshStream stream(kLatticeFormGouraudTriangleMeshShading, funcs,
467 pShadingStream, pCS);
468 if (!stream.Load())
469 return;
470
471 std::vector<CPDF_MeshVertex> vertices[2];
472 vertices[0] = stream.ReadVertexRow(mtObject2Bitmap, row_verts);
473 if (vertices[0].empty())
474 return;
475
476 int last_index = 0;
477 while (1) {
478 vertices[1 - last_index] = stream.ReadVertexRow(mtObject2Bitmap, row_verts);
479 if (vertices[1 - last_index].empty())
480 return;
481
482 CPDF_MeshVertex triangle[3];
483 for (int i = 1; i < row_verts; ++i) {
484 triangle[0] = vertices[last_index][i];
485 triangle[1] = vertices[1 - last_index][i - 1];
486 triangle[2] = vertices[last_index][i - 1];
487 DrawGouraud(pBitmap, alpha, triangle);
488 triangle[2] = vertices[1 - last_index][i];
489 DrawGouraud(pBitmap, alpha, triangle);
490 }
491 last_index = 1 - last_index;
492 }
493 }
494
495 struct Coon_BezierCoeff {
496 float a, b, c, d;
FromPoints__anon34c0c4600111::Coon_BezierCoeff497 void FromPoints(float p0, float p1, float p2, float p3) {
498 a = -p0 + 3 * p1 - 3 * p2 + p3;
499 b = 3 * p0 - 6 * p1 + 3 * p2;
500 c = -3 * p0 + 3 * p1;
501 d = p0;
502 }
first_half__anon34c0c4600111::Coon_BezierCoeff503 Coon_BezierCoeff first_half() {
504 Coon_BezierCoeff result;
505 result.a = a / 8;
506 result.b = b / 4;
507 result.c = c / 2;
508 result.d = d;
509 return result;
510 }
second_half__anon34c0c4600111::Coon_BezierCoeff511 Coon_BezierCoeff second_half() {
512 Coon_BezierCoeff result;
513 result.a = a / 8;
514 result.b = 3 * a / 8 + b / 4;
515 result.c = 3 * a / 8 + b / 2 + c / 2;
516 result.d = a / 8 + b / 4 + c / 2 + d;
517 return result;
518 }
GetPoints__anon34c0c4600111::Coon_BezierCoeff519 void GetPoints(float p[4]) {
520 p[0] = d;
521 p[1] = c / 3 + p[0];
522 p[2] = b / 3 - p[0] + 2 * p[1];
523 p[3] = a + p[0] - 3 * p[1] + 3 * p[2];
524 }
GetPointsReverse__anon34c0c4600111::Coon_BezierCoeff525 void GetPointsReverse(float p[4]) {
526 p[3] = d;
527 p[2] = c / 3 + p[3];
528 p[1] = b / 3 - p[3] + 2 * p[2];
529 p[0] = a + p[3] - 3 * p[2] + 3 * p[1];
530 }
BezierInterpol__anon34c0c4600111::Coon_BezierCoeff531 void BezierInterpol(Coon_BezierCoeff& C1,
532 Coon_BezierCoeff& C2,
533 Coon_BezierCoeff& D1,
534 Coon_BezierCoeff& D2) {
535 a = (D1.a + D2.a) / 2;
536 b = (D1.b + D2.b) / 2;
537 c = (D1.c + D2.c) / 2 - (C1.a / 8 + C1.b / 4 + C1.c / 2) +
538 (C2.a / 8 + C2.b / 4) + (-C1.d + D2.d) / 2 - (C2.a + C2.b) / 2;
539 d = C1.a / 8 + C1.b / 4 + C1.c / 2 + C1.d;
540 }
Distance__anon34c0c4600111::Coon_BezierCoeff541 float Distance() {
542 float dis = a + b + c;
543 return dis < 0 ? -dis : dis;
544 }
545 };
546
547 struct Coon_Bezier {
548 Coon_BezierCoeff x, y;
FromPoints__anon34c0c4600111::Coon_Bezier549 void FromPoints(float x0,
550 float y0,
551 float x1,
552 float y1,
553 float x2,
554 float y2,
555 float x3,
556 float y3) {
557 x.FromPoints(x0, x1, x2, x3);
558 y.FromPoints(y0, y1, y2, y3);
559 }
560
first_half__anon34c0c4600111::Coon_Bezier561 Coon_Bezier first_half() {
562 Coon_Bezier result;
563 result.x = x.first_half();
564 result.y = y.first_half();
565 return result;
566 }
567
second_half__anon34c0c4600111::Coon_Bezier568 Coon_Bezier second_half() {
569 Coon_Bezier result;
570 result.x = x.second_half();
571 result.y = y.second_half();
572 return result;
573 }
574
BezierInterpol__anon34c0c4600111::Coon_Bezier575 void BezierInterpol(Coon_Bezier& C1,
576 Coon_Bezier& C2,
577 Coon_Bezier& D1,
578 Coon_Bezier& D2) {
579 x.BezierInterpol(C1.x, C2.x, D1.x, D2.x);
580 y.BezierInterpol(C1.y, C2.y, D1.y, D2.y);
581 }
582
GetPoints__anon34c0c4600111::Coon_Bezier583 void GetPoints(std::vector<FX_PATHPOINT>& pPoints, size_t start_idx) {
584 float p[4];
585 int i;
586 x.GetPoints(p);
587 for (i = 0; i < 4; i++)
588 pPoints[start_idx + i].m_Point.x = p[i];
589
590 y.GetPoints(p);
591 for (i = 0; i < 4; i++)
592 pPoints[start_idx + i].m_Point.y = p[i];
593 }
594
GetPointsReverse__anon34c0c4600111::Coon_Bezier595 void GetPointsReverse(std::vector<FX_PATHPOINT>& pPoints, size_t start_idx) {
596 float p[4];
597 int i;
598 x.GetPointsReverse(p);
599 for (i = 0; i < 4; i++)
600 pPoints[i + start_idx].m_Point.x = p[i];
601
602 y.GetPointsReverse(p);
603 for (i = 0; i < 4; i++)
604 pPoints[i + start_idx].m_Point.y = p[i];
605 }
606
Distance__anon34c0c4600111::Coon_Bezier607 float Distance() { return x.Distance() + y.Distance(); }
608 };
609
Interpolate(int p1,int p2,int delta1,int delta2,bool * overflow)610 int Interpolate(int p1, int p2, int delta1, int delta2, bool* overflow) {
611 pdfium::base::CheckedNumeric<int> p = p2;
612 p -= p1;
613 p *= delta1;
614 p /= delta2;
615 p += p1;
616 if (!p.IsValid())
617 *overflow = true;
618 return p.ValueOrDefault(0);
619 }
620
BiInterpolImpl(int c0,int c1,int c2,int c3,int x,int y,int x_scale,int y_scale,bool * overflow)621 int BiInterpolImpl(int c0,
622 int c1,
623 int c2,
624 int c3,
625 int x,
626 int y,
627 int x_scale,
628 int y_scale,
629 bool* overflow) {
630 int x1 = Interpolate(c0, c3, x, x_scale, overflow);
631 int x2 = Interpolate(c1, c2, x, x_scale, overflow);
632 return Interpolate(x1, x2, y, y_scale, overflow);
633 }
634
635 struct Coon_Color {
Coon_Color__anon34c0c4600111::Coon_Color636 Coon_Color() { memset(comp, 0, sizeof(int) * 3); }
637
638 // Returns true if successful, false if overflow detected.
BiInterpol__anon34c0c4600111::Coon_Color639 bool BiInterpol(Coon_Color colors[4],
640 int x,
641 int y,
642 int x_scale,
643 int y_scale) {
644 bool overflow = false;
645 for (int i = 0; i < 3; i++) {
646 comp[i] = BiInterpolImpl(colors[0].comp[i], colors[1].comp[i],
647 colors[2].comp[i], colors[3].comp[i], x, y,
648 x_scale, y_scale, &overflow);
649 }
650 return !overflow;
651 }
652
Distance__anon34c0c4600111::Coon_Color653 int Distance(Coon_Color& o) {
654 return std::max({abs(comp[0] - o.comp[0]), abs(comp[1] - o.comp[1]),
655 abs(comp[2] - o.comp[2])});
656 }
657
658 int comp[3];
659 };
660
661 #define COONCOLOR_THRESHOLD 4
662 struct CPDF_PatchDrawer {
Draw__anon34c0c4600111::CPDF_PatchDrawer663 void Draw(int x_scale,
664 int y_scale,
665 int left,
666 int bottom,
667 Coon_Bezier C1,
668 Coon_Bezier C2,
669 Coon_Bezier D1,
670 Coon_Bezier D2) {
671 bool bSmall = C1.Distance() < 2 && C2.Distance() < 2 && D1.Distance() < 2 &&
672 D2.Distance() < 2;
673 Coon_Color div_colors[4];
674 int d_bottom = 0;
675 int d_left = 0;
676 int d_top = 0;
677 int d_right = 0;
678 if (!div_colors[0].BiInterpol(patch_colors, left, bottom, x_scale,
679 y_scale)) {
680 return;
681 }
682 if (!bSmall) {
683 if (!div_colors[1].BiInterpol(patch_colors, left, bottom + 1, x_scale,
684 y_scale)) {
685 return;
686 }
687 if (!div_colors[2].BiInterpol(patch_colors, left + 1, bottom + 1, x_scale,
688 y_scale)) {
689 return;
690 }
691 if (!div_colors[3].BiInterpol(patch_colors, left + 1, bottom, x_scale,
692 y_scale)) {
693 return;
694 }
695 d_bottom = div_colors[3].Distance(div_colors[0]);
696 d_left = div_colors[1].Distance(div_colors[0]);
697 d_top = div_colors[1].Distance(div_colors[2]);
698 d_right = div_colors[2].Distance(div_colors[3]);
699 }
700
701 if (bSmall ||
702 (d_bottom < COONCOLOR_THRESHOLD && d_left < COONCOLOR_THRESHOLD &&
703 d_top < COONCOLOR_THRESHOLD && d_right < COONCOLOR_THRESHOLD)) {
704 std::vector<FX_PATHPOINT>& pPoints = path.GetPoints();
705 C1.GetPoints(pPoints, 0);
706 D2.GetPoints(pPoints, 3);
707 C2.GetPointsReverse(pPoints, 6);
708 D1.GetPointsReverse(pPoints, 9);
709 int fillFlags = FXFILL_WINDING | FXFILL_FULLCOVER;
710 if (bNoPathSmooth)
711 fillFlags |= FXFILL_NOPATHSMOOTH;
712 pDevice->DrawPath(
713 &path, nullptr, nullptr,
714 ArgbEncode(alpha, div_colors[0].comp[0], div_colors[0].comp[1],
715 div_colors[0].comp[2]),
716 0, fillFlags);
717 } else {
718 if (d_bottom < COONCOLOR_THRESHOLD && d_top < COONCOLOR_THRESHOLD) {
719 Coon_Bezier m1;
720 m1.BezierInterpol(D1, D2, C1, C2);
721 y_scale *= 2;
722 bottom *= 2;
723 Draw(x_scale, y_scale, left, bottom, C1, m1, D1.first_half(),
724 D2.first_half());
725 Draw(x_scale, y_scale, left, bottom + 1, m1, C2, D1.second_half(),
726 D2.second_half());
727 } else if (d_left < COONCOLOR_THRESHOLD &&
728 d_right < COONCOLOR_THRESHOLD) {
729 Coon_Bezier m2;
730 m2.BezierInterpol(C1, C2, D1, D2);
731 x_scale *= 2;
732 left *= 2;
733 Draw(x_scale, y_scale, left, bottom, C1.first_half(), C2.first_half(),
734 D1, m2);
735 Draw(x_scale, y_scale, left + 1, bottom, C1.second_half(),
736 C2.second_half(), m2, D2);
737 } else {
738 Coon_Bezier m1, m2;
739 m1.BezierInterpol(D1, D2, C1, C2);
740 m2.BezierInterpol(C1, C2, D1, D2);
741 Coon_Bezier m1f = m1.first_half();
742 Coon_Bezier m1s = m1.second_half();
743 Coon_Bezier m2f = m2.first_half();
744 Coon_Bezier m2s = m2.second_half();
745 x_scale *= 2;
746 y_scale *= 2;
747 left *= 2;
748 bottom *= 2;
749 Draw(x_scale, y_scale, left, bottom, C1.first_half(), m1f,
750 D1.first_half(), m2f);
751 Draw(x_scale, y_scale, left, bottom + 1, m1f, C2.first_half(),
752 D1.second_half(), m2s);
753 Draw(x_scale, y_scale, left + 1, bottom, C1.second_half(), m1s, m2f,
754 D2.first_half());
755 Draw(x_scale, y_scale, left + 1, bottom + 1, m1s, C2.second_half(), m2s,
756 D2.second_half());
757 }
758 }
759 }
760
761 int max_delta;
762 CFX_PathData path;
763 CFX_RenderDevice* pDevice;
764 int bNoPathSmooth;
765 int alpha;
766 Coon_Color patch_colors[4];
767 };
768
DrawCoonPatchMeshes(ShadingType type,const RetainPtr<CFX_DIBitmap> & pBitmap,const CFX_Matrix & mtObject2Bitmap,const CPDF_Stream * pShadingStream,const std::vector<std::unique_ptr<CPDF_Function>> & funcs,const RetainPtr<CPDF_ColorSpace> & pCS,bool bNoPathSmooth,int alpha)769 void DrawCoonPatchMeshes(
770 ShadingType type,
771 const RetainPtr<CFX_DIBitmap>& pBitmap,
772 const CFX_Matrix& mtObject2Bitmap,
773 const CPDF_Stream* pShadingStream,
774 const std::vector<std::unique_ptr<CPDF_Function>>& funcs,
775 const RetainPtr<CPDF_ColorSpace>& pCS,
776 bool bNoPathSmooth,
777 int alpha) {
778 ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
779 ASSERT(type == kCoonsPatchMeshShading ||
780 type == kTensorProductPatchMeshShading);
781
782 CFX_DefaultRenderDevice device;
783 device.Attach(pBitmap, false, nullptr, false);
784 CPDF_MeshStream stream(type, funcs, pShadingStream, pCS);
785 if (!stream.Load())
786 return;
787
788 CPDF_PatchDrawer patch;
789 patch.alpha = alpha;
790 patch.pDevice = &device;
791 patch.bNoPathSmooth = bNoPathSmooth;
792
793 for (int i = 0; i < 13; i++) {
794 patch.path.AppendPoint(
795 CFX_PointF(), i == 0 ? FXPT_TYPE::MoveTo : FXPT_TYPE::BezierTo, false);
796 }
797
798 CFX_PointF coords[16];
799 int point_count = type == kTensorProductPatchMeshShading ? 16 : 12;
800 while (!stream.BitStream()->IsEOF()) {
801 if (!stream.CanReadFlag())
802 break;
803 uint32_t flag = stream.ReadFlag();
804 int iStartPoint = 0, iStartColor = 0, i = 0;
805 if (flag) {
806 iStartPoint = 4;
807 iStartColor = 2;
808 CFX_PointF tempCoords[4];
809 for (i = 0; i < 4; i++) {
810 tempCoords[i] = coords[(flag * 3 + i) % 12];
811 }
812 memcpy(coords, tempCoords, sizeof(tempCoords));
813 Coon_Color tempColors[2];
814 tempColors[0] = patch.patch_colors[flag];
815 tempColors[1] = patch.patch_colors[(flag + 1) % 4];
816 memcpy(patch.patch_colors, tempColors, sizeof(Coon_Color) * 2);
817 }
818 for (i = iStartPoint; i < point_count; i++) {
819 if (!stream.CanReadCoords())
820 break;
821 coords[i] = mtObject2Bitmap.Transform(stream.ReadCoords());
822 }
823
824 for (i = iStartColor; i < 4; i++) {
825 if (!stream.CanReadColor())
826 break;
827
828 float r;
829 float g;
830 float b;
831 std::tie(r, g, b) = stream.ReadColor();
832
833 patch.patch_colors[i].comp[0] = (int32_t)(r * 255);
834 patch.patch_colors[i].comp[1] = (int32_t)(g * 255);
835 patch.patch_colors[i].comp[2] = (int32_t)(b * 255);
836 }
837 CFX_FloatRect bbox = CFX_FloatRect::GetBBox(coords, point_count);
838 if (bbox.right <= 0 || bbox.left >= (float)pBitmap->GetWidth() ||
839 bbox.top <= 0 || bbox.bottom >= (float)pBitmap->GetHeight()) {
840 continue;
841 }
842 Coon_Bezier C1, C2, D1, D2;
843 C1.FromPoints(coords[0].x, coords[0].y, coords[11].x, coords[11].y,
844 coords[10].x, coords[10].y, coords[9].x, coords[9].y);
845 C2.FromPoints(coords[3].x, coords[3].y, coords[4].x, coords[4].y,
846 coords[5].x, coords[5].y, coords[6].x, coords[6].y);
847 D1.FromPoints(coords[0].x, coords[0].y, coords[1].x, coords[1].y,
848 coords[2].x, coords[2].y, coords[3].x, coords[3].y);
849 D2.FromPoints(coords[9].x, coords[9].y, coords[8].x, coords[8].y,
850 coords[7].x, coords[7].y, coords[6].x, coords[6].y);
851 patch.Draw(1, 1, 0, 0, C1, C2, D1, D2);
852 }
853 }
854
855 } // namespace
856
857 // static
Draw(CFX_RenderDevice * pDevice,CPDF_RenderContext * pContext,const CPDF_PageObject * pCurObj,const CPDF_ShadingPattern * pPattern,const CFX_Matrix & mtMatrix,const FX_RECT & clip_rect,int alpha,const CPDF_RenderOptions & options)858 void CPDF_RenderShading::Draw(CFX_RenderDevice* pDevice,
859 CPDF_RenderContext* pContext,
860 const CPDF_PageObject* pCurObj,
861 const CPDF_ShadingPattern* pPattern,
862 const CFX_Matrix& mtMatrix,
863 const FX_RECT& clip_rect,
864 int alpha,
865 const CPDF_RenderOptions& options) {
866 const auto& funcs = pPattern->GetFuncs();
867 const CPDF_Dictionary* pDict = pPattern->GetShadingObject()->GetDict();
868 RetainPtr<CPDF_ColorSpace> pColorSpace = pPattern->GetCS();
869 if (!pColorSpace)
870 return;
871
872 FX_ARGB background = 0;
873 if (!pPattern->IsShadingObject() && pDict->KeyExist("Background")) {
874 const CPDF_Array* pBackColor = pDict->GetArrayFor("Background");
875 if (pBackColor && pBackColor->size() >= pColorSpace->CountComponents()) {
876 std::vector<float> comps =
877 ReadArrayElementsToVector(pBackColor, pColorSpace->CountComponents());
878
879 float R = 0.0f;
880 float G = 0.0f;
881 float B = 0.0f;
882 pColorSpace->GetRGB(comps.data(), &R, &G, &B);
883 background = ArgbEncode(255, (int32_t)(R * 255), (int32_t)(G * 255),
884 (int32_t)(B * 255));
885 }
886 }
887 FX_RECT clip_rect_bbox = clip_rect;
888 if (pDict->KeyExist("BBox")) {
889 clip_rect_bbox.Intersect(
890 mtMatrix.TransformRect(pDict->GetRectFor("BBox")).GetOuterRect());
891 }
892 bool bAlphaMode = options.ColorModeIs(CPDF_RenderOptions::kAlpha);
893 if (pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_SHADING &&
894 pDevice->GetDeviceDriver()->DrawShading(
895 pPattern, &mtMatrix, clip_rect_bbox, alpha, bAlphaMode)) {
896 return;
897 }
898 CPDF_DeviceBuffer buffer(pContext, pDevice, clip_rect_bbox, pCurObj, 150);
899 if (!buffer.Initialize())
900 return;
901
902 CFX_Matrix FinalMatrix = mtMatrix * buffer.GetMatrix();
903 RetainPtr<CFX_DIBitmap> pBitmap = buffer.GetBitmap();
904 if (!pBitmap->GetBuffer())
905 return;
906
907 pBitmap->Clear(background);
908 switch (pPattern->GetShadingType()) {
909 case kInvalidShading:
910 case kMaxShading:
911 return;
912 case kFunctionBasedShading:
913 DrawFuncShading(pBitmap, FinalMatrix, pDict, funcs, pColorSpace, alpha);
914 break;
915 case kAxialShading:
916 DrawAxialShading(pBitmap, FinalMatrix, pDict, funcs, pColorSpace, alpha);
917 break;
918 case kRadialShading:
919 DrawRadialShading(pBitmap, FinalMatrix, pDict, funcs, pColorSpace, alpha);
920 break;
921 case kFreeFormGouraudTriangleMeshShading: {
922 // The shading object can be a stream or a dictionary. We do not handle
923 // the case of dictionary at the moment.
924 if (const CPDF_Stream* pStream = ToStream(pPattern->GetShadingObject())) {
925 DrawFreeGouraudShading(pBitmap, FinalMatrix, pStream, funcs,
926 pColorSpace, alpha);
927 }
928 } break;
929 case kLatticeFormGouraudTriangleMeshShading: {
930 // The shading object can be a stream or a dictionary. We do not handle
931 // the case of dictionary at the moment.
932 if (const CPDF_Stream* pStream = ToStream(pPattern->GetShadingObject())) {
933 DrawLatticeGouraudShading(pBitmap, FinalMatrix, pStream, funcs,
934 pColorSpace, alpha);
935 }
936 } break;
937 case kCoonsPatchMeshShading:
938 case kTensorProductPatchMeshShading: {
939 // The shading object can be a stream or a dictionary. We do not handle
940 // the case of dictionary at the moment.
941 if (const CPDF_Stream* pStream = ToStream(pPattern->GetShadingObject())) {
942 DrawCoonPatchMeshes(pPattern->GetShadingType(), pBitmap, FinalMatrix,
943 pStream, funcs, pColorSpace,
944 options.GetOptions().bNoPathSmooth, alpha);
945 }
946 } break;
947 }
948 if (bAlphaMode)
949 pBitmap->LoadChannelFromAlpha(FXDIB_Red, pBitmap);
950
951 if (options.ColorModeIs(CPDF_RenderOptions::kGray))
952 pBitmap->ConvertColorScale(0, 0xffffff);
953 buffer.OutputToDevice();
954 }
955