Glop.h revision 30036092b40badecbe64d9c2bff4850132147f78 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_HWUI_GLOP_H
18#define ANDROID_HWUI_GLOP_H
19
20#include "FloatColor.h"
21#include "Matrix.h"
22#include "Rect.h"
23#include "utils/Macros.h"
24
25#include <GLES2/gl2.h>
26#include <GLES2/gl2ext.h>
27#include <SkXfermode.h>
28
29namespace android {
30namespace uirenderer {
31
32class Program;
33class RoundRectClipState;
34
35/*
36 * Enumerates optional vertex attributes
37 *
38 * Position is always enabled by MeshState, these other attributes
39 * are enabled/disabled dynamically based on mesh content.
40 */
41enum VertexAttribFlags {
42    kNone_Attrib = 0,
43    kTextureCoord_Attrib = 1 << 0,
44    kColor_Attrib = 1 << 1,
45    kAlpha_Attrib = 1 << 2,
46};
47
48/**
49 * Structure containing all data required to issue an OpenGL draw
50 *
51 * Includes all of the mesh, fill, and GL state required to perform
52 * the operation. Pieces of data are either directly copied into the
53 * structure, or stored as a pointer or GL object reference to data
54 * managed.
55 *
56 * Eventually, a Glop should be able to be drawn multiple times from
57 * a single construction, up until GL context destruction. Currently,
58 * vertex/index/Texture/RoundRectClipState pointers prevent this from
59 * being safe.
60 */
61// TODO: PREVENT_COPY_AND_ASSIGN(...) or similar
62struct Glop {
63    /*
64     * Stores mesh - vertex and index data.
65     *
66     * buffer objects and void*s are mutually exclusive
67     * indices are optional, currently only GL_UNSIGNED_SHORT supported
68     */
69    struct Mesh {
70        VertexAttribFlags vertexFlags;
71        GLuint primitiveMode; // GL_TRIANGLES and GL_TRIANGLE_STRIP supported
72        GLuint vertexBufferObject;
73        GLuint indexBufferObject;
74        const void* vertices;
75        const void* indices;
76        int elementCount;
77        GLsizei stride;
78        GLvoid* texCoordOffset;
79        TextureVertex mappedVertices[4];
80    } mesh;
81
82    struct Fill {
83        Program* program;
84
85        Texture* texture;
86        GLenum textureFilter;
87        GLenum textureClamp;
88
89        bool colorEnabled;
90        FloatColor color;
91
92        /* TODO
93        union shader {
94            //...
95        }; TODO
96        */
97        ProgramDescription::ColorFilterMode filterMode;
98        union Filter {
99            struct Matrix {
100                float matrix[16];
101                float vector[4];
102            } matrix;
103            FloatColor color;
104        } filter;
105    } fill;
106
107    struct Transform {
108        Matrix4 ortho; // TODO: out of op, since this is static per FBO
109        Matrix4 modelView;
110        Matrix4 canvas;
111        bool fudgingOffset;
112    } transform;
113
114    const RoundRectClipState* roundRectClipState;
115
116    /**
117     * Blending to be used by this draw - both GL_NONE if blending is disabled.
118     *
119     * Defined by fill step, but can be force-enabled by presence of kAlpha_Attrib
120     */
121    struct Blend {
122        GLenum src;
123        GLenum dst;
124    } blend;
125
126    /**
127     * Bounds of the drawing command in layer space. Only mapped into layer
128     * space once GlopBuilder::build() is called.
129     */
130    Rect bounds;
131
132    /**
133     * Additional render state to enumerate:
134     * - scissor + (bits for whether each of LTRB needed?)
135     * - stencil mode (draw into, mask, count, etc)
136     */
137};
138
139} /* namespace uirenderer */
140} /* namespace android */
141
142#endif // ANDROID_HWUI_GLOP_H
143