1 /*
2  * Copyright 2016 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "SkRasterPipeline.h"
9 #include "SkPM4f.h"
10 #include "SkPM4fPriv.h"
11 #include "../jumper/SkJumper.h"
12 #include <algorithm>
13 
SkRasterPipeline(SkArenaAlloc * alloc)14 SkRasterPipeline::SkRasterPipeline(SkArenaAlloc* alloc) : fAlloc(alloc) {
15     this->reset();
16 }
reset()17 void SkRasterPipeline::reset() {
18     fStages      = nullptr;
19     fNumStages   = 0;
20     fSlotsNeeded = 1;  // We always need one extra slot for just_return().
21 }
22 
append(StockStage stage,void * ctx)23 void SkRasterPipeline::append(StockStage stage, void* ctx) {
24     SkASSERT(stage != uniform_color);  // Please use append_constant_color().
25     SkASSERT(stage != seed_shader);    // Please use append_seed_shader().
26     this->unchecked_append(stage, ctx);
27 }
unchecked_append(StockStage stage,void * ctx)28 void SkRasterPipeline::unchecked_append(StockStage stage, void* ctx) {
29     fStages = fAlloc->make<StageList>( StageList{fStages, stage, ctx} );
30     fNumStages   += 1;
31     fSlotsNeeded += ctx ? 2 : 1;
32 }
33 
extend(const SkRasterPipeline & src)34 void SkRasterPipeline::extend(const SkRasterPipeline& src) {
35     if (src.empty()) {
36         return;
37     }
38     auto stages = fAlloc->makeArrayDefault<StageList>(src.fNumStages);
39 
40     int n = src.fNumStages;
41     const StageList* st = src.fStages;
42     while (n --> 1) {
43         stages[n]      = *st;
44         stages[n].prev = &stages[n-1];
45         st = st->prev;
46     }
47     stages[0]      = *st;
48     stages[0].prev = fStages;
49 
50     fStages = &stages[src.fNumStages - 1];
51     fNumStages   += src.fNumStages;
52     fSlotsNeeded += src.fSlotsNeeded - 1;  // Don't double count just_returns().
53 }
54 
dump() const55 void SkRasterPipeline::dump() const {
56     SkDebugf("SkRasterPipeline, %d stages\n", fNumStages);
57     std::vector<const char*> stages;
58     for (auto st = fStages; st; st = st->prev) {
59         const char* name = "";
60         switch (st->stage) {
61         #define M(x) case x: name = #x; break;
62             SK_RASTER_PIPELINE_STAGES(M)
63         #undef M
64         }
65         stages.push_back(name);
66     }
67     std::reverse(stages.begin(), stages.end());
68     for (const char* name : stages) {
69         SkDebugf("\t%s\n", name);
70     }
71     SkDebugf("\n");
72 }
73 
74 //#define TRACK_COLOR_HISTOGRAM
75 #ifdef TRACK_COLOR_HISTOGRAM
76     static int gBlack;
77     static int gWhite;
78     static int gColor;
79     #define INC_BLACK   gBlack++
80     #define INC_WHITE   gWhite++
81     #define INC_COLOR   gColor++
82 #else
83     #define INC_BLACK
84     #define INC_WHITE
85     #define INC_COLOR
86 #endif
87 
append_constant_color(SkArenaAlloc * alloc,const float rgba[4])88 void SkRasterPipeline::append_constant_color(SkArenaAlloc* alloc, const float rgba[4]) {
89     SkASSERT(0 <= rgba[0] && rgba[0] <= 1);
90     SkASSERT(0 <= rgba[1] && rgba[1] <= 1);
91     SkASSERT(0 <= rgba[2] && rgba[2] <= 1);
92     SkASSERT(0 <= rgba[3] && rgba[3] <= 1);
93 
94     if (rgba[0] == 0 && rgba[1] == 0 && rgba[2] == 0 && rgba[3] == 1) {
95         this->append(black_color);
96         INC_BLACK;
97     } else if (rgba[0] == 1 && rgba[1] == 1 && rgba[2] == 1 && rgba[3] == 1) {
98         this->append(white_color);
99         INC_WHITE;
100     } else {
101         auto ctx = alloc->make<SkJumper_UniformColorCtx>();
102         Sk4f color = Sk4f::Load(rgba);
103         color.store(&ctx->r);
104 
105         // To make loads more direct, we store 8-bit values in 16-bit slots.
106         color = color * 255.0f + 0.5f;
107         ctx->rgba[0] = (uint16_t)color[0];
108         ctx->rgba[1] = (uint16_t)color[1];
109         ctx->rgba[2] = (uint16_t)color[2];
110         ctx->rgba[3] = (uint16_t)color[3];
111 
112         this->unchecked_append(uniform_color, ctx);
113         INC_COLOR;
114     }
115 
116 #ifdef TRACK_COLOR_HISTOGRAM
117     SkDebugf("B=%d W=%d C=%d\n", gBlack, gWhite, gColor);
118 #endif
119 }
120 
121 #undef INC_BLACK
122 #undef INC_WHITE
123 #undef INC_COLOR
124 
125 //static int gCounts[5] = { 0, 0, 0, 0, 0 };
126 
append_matrix(SkArenaAlloc * alloc,const SkMatrix & matrix)127 void SkRasterPipeline::append_matrix(SkArenaAlloc* alloc, const SkMatrix& matrix) {
128     SkMatrix::TypeMask mt = matrix.getType();
129 #if 0
130     if (mt > 4) mt = 4;
131     gCounts[mt] += 1;
132     SkDebugf("matrices: %d %d %d %d %d\n",
133              gCounts[0], gCounts[1], gCounts[2], gCounts[3], gCounts[4]);
134 #endif
135 
136     // Based on a histogram of skps, we determined the following special cases were common, more
137     // or fewer can be used if client behaviors change.
138 
139     if (mt == SkMatrix::kIdentity_Mask) {
140         return;
141     }
142     if (mt == SkMatrix::kTranslate_Mask) {
143         float* trans = alloc->makeArrayDefault<float>(2);
144         trans[0] = matrix.getTranslateX();
145         trans[1] = matrix.getTranslateY();
146         this->append(SkRasterPipeline::matrix_translate, trans);
147     } else if ((mt | (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) ==
148                      (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) {
149         float* scaleTrans = alloc->makeArrayDefault<float>(4);
150         scaleTrans[0] = matrix.getScaleX();
151         scaleTrans[1] = matrix.getScaleY();
152         scaleTrans[2] = matrix.getTranslateX();
153         scaleTrans[3] = matrix.getTranslateY();
154         this->append(SkRasterPipeline::matrix_scale_translate, scaleTrans);
155     } else {
156         float* storage = alloc->makeArrayDefault<float>(9);
157         if (matrix.asAffine(storage)) {
158             // note: asAffine and the 2x3 stage really only need 6 entries
159             this->append(SkRasterPipeline::matrix_2x3, storage);
160         } else {
161             matrix.get9(storage);
162             this->append(SkRasterPipeline::matrix_perspective, storage);
163         }
164     }
165 }
166 
append_seed_shader()167 void SkRasterPipeline::append_seed_shader() {
168     static const float iota[] = {
169         0.5f, 1.5f, 2.5f, 3.5f, 4.5f, 5.5f, 6.5f, 7.5f,
170         8.5f, 9.5f,10.5f,11.5f,12.5f,13.5f,14.5f,15.5f,
171     };
172     this->unchecked_append(SkRasterPipeline::seed_shader, const_cast<float*>(iota));
173 }
174