| /* |
| * Copyright 2016 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkRasterPipeline_DEFINED |
| #define SkRasterPipeline_DEFINED |
| |
| #include "SkNx.h" |
| #include "SkTArray.h" |
| #include "SkTypes.h" |
| #include <functional> |
| |
| /** |
| * SkRasterPipeline provides a cheap way to chain together a pixel processing pipeline. |
| * |
| * It's particularly designed for situations where the potential pipeline is extremely |
| * combinatoric: {N dst formats} x {M source formats} x {K mask formats} x {C transfer modes} ... |
| * No one wants to write specialized routines for all those combinations, and if we did, we'd |
| * end up bloating our code size dramatically. SkRasterPipeline stages can be chained together |
| * at runtime, so we can scale this problem linearly rather than combinatorically. |
| * |
| * Each stage is represented by a function conforming to a common interface, SkRasterPipeline::Fn, |
| * and by an arbitrary context pointer. Fn's arguments, and sometimes custom calling convention, |
| * are designed to maximize the amount of data we can pass along the pipeline cheaply. |
| * On many machines all arguments stay in registers the entire time. |
| * |
| * The meaning of the arguments to Fn are sometimes fixed: |
| * - The Stage* always represents the current stage, mainly providing access to ctx(). |
| * - The first size_t is always the destination x coordinate. |
| * (If you need y, put it in your context.) |
| * - The second size_t is always tail: 0 when working on a full 4-pixel slab, |
| * or 1..3 when using only the bottom 1..3 lanes of each register. |
| * - By the time the shader's done, the first four vectors should hold source red, |
| * green, blue, and alpha, up to 4 pixels' worth each. |
| * |
| * Sometimes arguments are flexible: |
| * - In the shader, the first four vectors can be used for anything, e.g. sample coordinates. |
| * - The last four vectors are scratch registers that can be used to communicate between |
| * stages; transfer modes use these to hold the original destination pixel components. |
| * |
| * On some platforms the last four vectors are slower to work with than the other arguments. |
| * |
| * When done mutating its arguments and/or context, a stage can either: |
| * 1) call st->next() with its mutated arguments, chaining to the next stage of the pipeline; or |
| * 2) return, indicating the pipeline is complete for these pixels. |
| * |
| * Some stages that typically return are those that write a color to a destination pointer, |
| * but any stage can short-circuit the rest of the pipeline by returning instead of calling next(). |
| */ |
| |
| // TODO: There may be a better place to stuff tail, e.g. in the bottom alignment bits of |
| // the Stage*. This mostly matters on 64-bit Windows where every register is precious. |
| |
| #define SK_RASTER_PIPELINE_STAGES(M) \ |
| M(trace) M(registers) \ |
| M(move_src_dst) M(swap_src_dst) \ |
| M(clamp_0) M(clamp_a) M(clamp_1) M(unpremul) M(premul) \ |
| M(constant_color) M(store_f32) \ |
| M(load_s_565) M(load_d_565) M(store_565) \ |
| M(load_s_srgb) M(load_d_srgb) M(store_srgb) \ |
| M(load_s_f16) M(load_d_f16) M(store_f16) \ |
| M(load_s_8888) M(store_8888) \ |
| M(scale_u8) M(scale_constant_float) \ |
| M(lerp_u8) M(lerp_565) M(lerp_constant_float) \ |
| M(dst) \ |
| M(dstatop) M(dstin) M(dstout) M(dstover) \ |
| M(srcatop) M(srcin) M(srcout) M(srcover) \ |
| M(clear) M(modulate) M(multiply) M(plus_) M(screen) M(xor_) \ |
| M(colorburn) M(colordodge) M(darken) M(difference) \ |
| M(exclusion) M(hardlight) M(lighten) M(overlay) M(softlight) \ |
| M(luminance_to_alpha) \ |
| M(matrix_2x3) M(matrix_3x4) M(matrix_4x5) \ |
| M(parametric_r) M(parametric_g) M(parametric_b) \ |
| M(table_r) M(table_g) M(table_b) \ |
| M(color_lookup_table) M(lab_to_xyz) M(swap_rb) \ |
| M(clamp_x) M(mirror_x) M(repeat_x) \ |
| M(clamp_y) M(mirror_y) M(repeat_y) \ |
| M(nearest_565) M(nearest_8888) M(nearest_srgb) M(nearest_f16) |
| |
| class SkRasterPipeline { |
| public: |
| // No pipeline may be more than kMaxStages long. |
| static const int kMaxStages = 32; |
| |
| SkRasterPipeline(); |
| |
| enum StockStage { |
| #define M(stage) stage, |
| SK_RASTER_PIPELINE_STAGES(M) |
| #undef M |
| }; |
| void append(StockStage, void* = nullptr); |
| void append(StockStage stage, const void* ctx) { this->append(stage, const_cast<void*>(ctx)); } |
| |
| // Append all stages to this pipeline. |
| void extend(const SkRasterPipeline&); |
| |
| // Runs the pipeline walking x through [x,x+n), holding y constant. |
| std::function<void(size_t x, size_t y, size_t n)> compile() const; |
| |
| void dump() const; |
| |
| struct Stage { |
| StockStage stage; |
| void* ctx; |
| }; |
| |
| private: |
| int fNum = 0; |
| Stage fStages[kMaxStages]; |
| }; |
| |
| #endif//SkRasterPipeline_DEFINED |