OpenGLRenderer.h revision 2542d199745cdf3ec910b8e3e4cff5851ed24e9b 
1/*
2 * Copyright (C) 2010 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_UI_OPENGL_RENDERER_H
18#define ANDROID_UI_OPENGL_RENDERER_H
19
20#include <GLES2/gl2.h>
21#include <GLES2/gl2ext.h>
22
23#include <SkBitmap.h>
24#include <SkMatrix.h>
25#include <SkPaint.h>
26#include <SkRegion.h>
27#include <SkShader.h>
28#include <SkXfermode.h>
29
30#include <utils/RefBase.h>
31#include <utils/ResourceTypes.h>
32
33#include "Extensions.h"
34#include "Matrix.h"
35#include "Program.h"
36#include "Rect.h"
37#include "Snapshot.h"
38#include "TextureCache.h"
39#include "LayerCache.h"
40#include "GradientCache.h"
41#include "PatchCache.h"
42#include "Vertex.h"
43#include "FontRenderer.h"
44#include "ProgramCache.h"
45#include "SkiaShader.h"
46#include "SkiaColorFilter.h"
47#include "PathCache.h"
48#include "TextDropShadowCache.h"
49
50namespace android {
51namespace uirenderer {
52
53///////////////////////////////////////////////////////////////////////////////
54// Renderer
55///////////////////////////////////////////////////////////////////////////////
56
57/**
58 * OpenGL renderer used to draw accelerated 2D graphics. The API is a
59 * simplified version of Skia's Canvas API.
60 */
61class OpenGLRenderer {
62public:
63    OpenGLRenderer();
64    ~OpenGLRenderer();
65
66    void setViewport(int width, int height);
67    void prepare();
68
69    int getSaveCount() const;
70    int save(int flags);
71    void restore();
72    void restoreToCount(int saveCount);
73
74    int saveLayer(float left, float top, float right, float bottom, const SkPaint* p, int flags);
75    int saveLayerAlpha(float left, float top, float right, float bottom, int alpha, int flags);
76
77    void translate(float dx, float dy);
78    void rotate(float degrees);
79    void scale(float sx, float sy);
80
81    void setMatrix(SkMatrix* matrix);
82    void getMatrix(SkMatrix* matrix);
83    void concatMatrix(SkMatrix* matrix);
84
85    const Rect& getClipBounds();
86    bool quickReject(float left, float top, float right, float bottom);
87    bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op);
88
89    void drawBitmap(SkBitmap* bitmap, float left, float top, const SkPaint* paint);
90    void drawBitmap(SkBitmap* bitmap, const SkMatrix* matrix, const SkPaint* paint);
91    void drawBitmap(SkBitmap* bitmap, float srcLeft, float srcTop, float srcRight, float srcBottom,
92            float dstLeft, float dstTop, float dstRight, float dstBottom, const SkPaint* paint);
93    void drawPatch(SkBitmap* bitmap, Res_png_9patch* patch, float left, float top,
94            float right, float bottom, const SkPaint* paint);
95    void drawColor(int color, SkXfermode::Mode mode);
96    void drawRect(float left, float top, float right, float bottom, const SkPaint* paint);
97    void drawPath(SkPath* path, SkPaint* paint);
98
99    void resetShader();
100    void setupShader(SkiaShader* shader);
101
102    void resetColorFilter();
103    void setupColorFilter(SkiaColorFilter* filter);
104
105    void resetShadow();
106    void setupShadow(float radius, float dx, float dy, int color);
107
108    void drawText(const char* text, int bytesCount, int count, float x, float y, SkPaint* paint);
109
110private:
111    /**
112     * Saves the current state of the renderer as a new snapshot.
113     * The new snapshot is saved in mSnapshot and the previous snapshot
114     * is linked from mSnapshot->previous.
115     *
116     * @return The new save count. This value can be passed to #restoreToCount()
117     */
118    int saveSnapshot();
119
120    /**
121     * Restores the current snapshot; mSnapshot becomes mSnapshot->previous.
122     *
123     * @return True if the clip was modified.
124     */
125    bool restoreSnapshot();
126
127    /**
128     * Sets the clipping rectangle using glScissor. The clip is defined by
129     * the current snapshot's clipRect member.
130     */
131    void setScissorFromClip();
132
133    /**
134     * Compose the layer defined in the current snapshot with the layer
135     * defined by the previous snapshot.
136     *
137     * The current snapshot *must* be a layer (flag kFlagIsLayer set.)
138     *
139     * @param curent The current snapshot containing the layer to compose
140     * @param previous The previous snapshot to compose the current layer with
141     */
142    void composeLayer(sp<Snapshot> current, sp<Snapshot> previous);
143
144    /**
145     * Creates a new layer stored in the specified snapshot.
146     *
147     * @param snapshot The snapshot associated with the new layer
148     * @param left The left coordinate of the layer
149     * @param top The top coordinate of the layer
150     * @param right The right coordinate of the layer
151     * @param bottom The bottom coordinate of the layer
152     * @param alpha The translucency of the layer
153     * @param mode The blending mode of the layer
154     * @param flags The layer save flags
155     *
156     * @return True if the layer was successfully created, false otherwise
157     */
158    bool createLayer(sp<Snapshot> snapshot, float left, float top, float right, float bottom,
159            int alpha, SkXfermode::Mode mode, int flags);
160
161    /**
162     * Draws a colored rectangle with the specified color. The specified coordinates
163     * are transformed by the current snapshot's transform matrix.
164     *
165     * @param left The left coordinate of the rectangle
166     * @param top The top coordinate of the rectangle
167     * @param right The right coordinate of the rectangle
168     * @param bottom The bottom coordinate of the rectangle
169     * @param color The rectangle's ARGB color, defined as a packed 32 bits word
170     * @param mode The Skia xfermode to use
171     * @param ignoreTransform True if the current transform should be ignored
172     */
173    void drawColorRect(float left, float top, float right, float bottom,
174    		int color, SkXfermode::Mode mode, bool ignoreTransform = false);
175
176    /**
177     * Draws a textured rectangle with the specified texture. The specified coordinates
178     * are transformed by the current snapshot's transform matrix.
179     *
180     * @param left The left coordinate of the rectangle
181     * @param top The top coordinate of the rectangle
182     * @param right The right coordinate of the rectangle
183     * @param bottom The bottom coordinate of the rectangle
184     * @param texture The texture name to map onto the rectangle
185     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
186     * @param mode The blending mode
187     * @param blend True if the texture contains an alpha channel
188     */
189    void drawTextureRect(float left, float top, float right, float bottom, GLuint texture,
190            float alpha, SkXfermode::Mode mode, bool blend);
191
192    /**
193     * Draws a textured rectangle with the specified texture. The specified coordinates
194     * are transformed by the current snapshot's transform matrix.
195     *
196     * @param left The left coordinate of the rectangle
197     * @param top The top coordinate of the rectangle
198     * @param right The right coordinate of the rectangle
199     * @param bottom The bottom coordinate of the rectangle
200     * @param texture The texture to use
201     * @param paint The paint containing the alpha, blending mode, etc.
202     */
203    void drawTextureRect(float left, float top, float right, float bottom,
204            const Texture* texture, const SkPaint* paint);
205
206    /**
207     * Draws a textured mesh with the specified texture. If the indices are omitted, the
208     * mesh is drawn as a simple quad.
209     *
210     * @param left The left coordinate of the rectangle
211     * @param top The top coordinate of the rectangle
212     * @param right The right coordinate of the rectangle
213     * @param bottom The bottom coordinate of the rectangle
214     * @param texture The texture name to map onto the rectangle
215     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
216     * @param mode The blending mode
217     * @param blend True if the texture contains an alpha channel
218     * @param vertices The vertices that define the mesh
219     * @param texCoords The texture coordinates of each vertex
220     * @param indices The indices of the vertices, can be NULL
221     * @param elementsCount The number of elements in the mesh, required by indices
222     */
223    void drawTextureMesh(float left, float top, float right, float bottom, GLuint texture,
224            float alpha, SkXfermode::Mode mode, bool blend,
225            GLvoid* vertices, GLvoid* texCoords, GLvoid* indices, GLsizei elementsCount = 0);
226
227    /**
228     * Prepares the renderer to draw the specified shadow.
229     *
230     * @param texture The shadow texture
231     * @param x The x coordinate of the shadow
232     * @param y The y coordinate of the shadow
233     * @param mode The blending mode
234     * @param alpha The alpha value
235     */
236    void setupShadow(const ShadowTexture* texture, float x, float y, SkXfermode::Mode mode,
237            float alpha);
238
239    /**
240     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
241     *
242     * @param texture The texture to render with
243     * @param textureUnit The texture unit to use, may be modified
244     * @param x The x coordinate of the rectangle to draw
245     * @param y The y coordinate of the rectangle to draw
246     * @param r The red component of the color
247     * @param g The green component of the color
248     * @param b The blue component of the color
249     * @param a The alpha component of the color
250     * @param mode The blending mode
251     * @param transforms True if the matrix passed to the shader should be multiplied
252     *        by the model-view matrix
253     * @param applyFilters Whether or not to take color filters and
254     *        shaders into account
255     */
256    void setupTextureAlpha8(const Texture* texture, GLuint& textureUnit, float x, float y,
257            float r, float g, float b, float a, SkXfermode::Mode mode, bool transforms,
258            bool applyFilters);
259
260    /**
261     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
262     *
263     * @param texture The texture to render with
264     * @param width The width of the texture
265     * @param height The height of the texture
266     * @param textureUnit The texture unit to use, may be modified
267     * @param x The x coordinate of the rectangle to draw
268     * @param y The y coordinate of the rectangle to draw
269     * @param r The red component of the color
270     * @param g The green component of the color
271     * @param b The blue component of the color
272     * @param a The alpha component of the color
273     * @param mode The blending mode
274     * @param transforms True if the matrix passed to the shader should be multiplied
275     *        by the model-view matrix
276     * @param applyFilters Whether or not to take color filters and
277     *        shaders into account
278     */
279    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
280            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
281            SkXfermode::Mode mode, bool transforms, bool applyFilters);
282
283    /**
284     * Draws text underline and strike-through if needed.
285     *
286     * @param text The text to decor
287     * @param bytesCount The number of bytes in the text
288     * @param length The length in pixels of the text, can be <= 0.0f to force a measurement
289     * @param x The x coordinate where the text will be drawn
290     * @param y The y coordinate where the text will be drawn
291     * @param paint The paint to draw the text with
292     */
293    void drawTextDecorations(const char* text, int bytesCount, float length,
294            float x, float y, SkPaint* paint);
295
296    /**
297     * Resets the texture coordinates stored in mMeshVertices. Setting the values
298     * back to default is achieved by calling:
299     *
300     * resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
301     *
302     * @param u1 The left coordinate of the texture
303     * @param v1 The bottom coordinate of the texture
304     * @param u2 The right coordinate of the texture
305     * @param v2 The top coordinate of the texture
306     */
307    void resetDrawTextureTexCoords(float u1, float v1, float u2, float v2);
308
309    /**
310     * Gets the alpha and xfermode out of a paint object. If the paint is null
311     * alpha will be 255 and the xfermode will be SRC_OVER.
312     *
313     * @param paint The paint to extract values from
314     * @param alpha Where to store the resulting alpha
315     * @param mode Where to store the resulting xfermode
316     */
317    inline void getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode);
318
319    /**
320     * Binds the specified texture with the specified wrap modes.
321     */
322    inline void bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit = 0);
323
324    /**
325     * Enable or disable blending as necessary. This function sets the appropriate
326     * blend function based on the specified xfermode.
327     */
328    inline void chooseBlending(bool blend, SkXfermode::Mode mode, bool isPremultiplied = true);
329
330    /**
331     * Use the specified program with the current GL context. If the program is already
332     * in use, it will not be bound again. If it is not in use, the current program is
333     * marked unused and the specified program becomes used and becomes the new
334     * current program.
335     *
336     * @param program The program to use
337     *
338     * @return true If the specified program was already in use, false otherwise.
339     */
340    inline bool useProgram(Program* program);
341
342    // Dimensions of the drawing surface
343    int mWidth, mHeight;
344
345    // Matrix used for ortho projection in shaders
346    mat4 mOrthoMatrix;
347
348    // Model-view matrix used to position/size objects
349    mat4 mModelView;
350
351    // Number of saved states
352    int mSaveCount;
353    // Base state
354    sp<Snapshot> mFirstSnapshot;
355    // Current state
356    sp<Snapshot> mSnapshot;
357
358    // Shaders
359    Program* mCurrentProgram;
360    SkiaShader* mShader;
361
362    // Color filters
363    SkiaColorFilter* mColorFilter;
364
365    // Used to draw textured quads
366    TextureVertex mMeshVertices[4];
367
368    // Last known blend state
369    bool mBlend;
370    GLenum mLastSrcMode;
371    GLenum mLastDstMode;
372
373    // GL extensions
374    Extensions mExtensions;
375
376    // Font renderer
377    FontRenderer mFontRenderer;
378
379    // Drop shadow
380    bool mHasShadow;
381    float mShadowRadius;
382    float mShadowDx;
383    float mShadowDy;
384    int mShadowColor;
385
386    // Various caches
387    TextureCache mTextureCache;
388    LayerCache mLayerCache;
389    GradientCache mGradientCache;
390    ProgramCache mProgramCache;
391    PathCache mPathCache;
392    PatchCache mPatchCache;
393    TextDropShadowCache mDropShadowCache;
394}; // class OpenGLRenderer
395
396}; // namespace uirenderer
397}; // namespace android
398
399#endif // ANDROID_UI_OPENGL_RENDERER_H
400