OpenGLRenderer.h revision 4bb942083a0d4db746adf95349108dd8ef842e32 
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/Vector.h>
32
33#include "Extensions.h"
34#include "Matrix.h"
35#include "Program.h"
36#include "Rect.h"
37#include "Snapshot.h"
38#include "Vertex.h"
39#include "SkiaShader.h"
40#include "SkiaColorFilter.h"
41#include "Caches.h"
42
43namespace android {
44namespace uirenderer {
45
46///////////////////////////////////////////////////////////////////////////////
47// Defines
48///////////////////////////////////////////////////////////////////////////////
49
50// Debug
51#define DEBUG_OPENGL 1
52
53///////////////////////////////////////////////////////////////////////////////
54// Renderer
55///////////////////////////////////////////////////////////////////////////////
56
57class DisplayListRenderer;
58
59/**
60 * OpenGL renderer used to draw accelerated 2D graphics. The API is a
61 * simplified version of Skia's Canvas API.
62 */
63class OpenGLRenderer {
64public:
65    OpenGLRenderer();
66    virtual ~OpenGLRenderer();
67
68    virtual void setViewport(int width, int height);
69
70    virtual void prepare(bool opaque);
71    virtual void finish();
72
73    virtual void acquireContext();
74    virtual void releaseContext();
75
76    int getSaveCount() const;
77    virtual int save(int flags);
78    virtual void restore();
79    virtual void restoreToCount(int saveCount);
80
81    virtual int saveLayer(float left, float top, float right, float bottom,
82            const SkPaint* p, int flags);
83    virtual int saveLayerAlpha(float left, float top, float right, float bottom,
84            int alpha, int flags);
85
86    virtual void translate(float dx, float dy);
87    virtual void rotate(float degrees);
88    virtual void scale(float sx, float sy);
89
90    void getMatrix(SkMatrix* matrix);
91    virtual void setMatrix(SkMatrix* matrix);
92    virtual void concatMatrix(SkMatrix* matrix);
93
94    const Rect& getClipBounds();
95    bool quickReject(float left, float top, float right, float bottom);
96    virtual bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op);
97
98    virtual void drawBitmap(SkBitmap* bitmap, float left, float top, const SkPaint* paint);
99    virtual void drawBitmap(SkBitmap* bitmap, const SkMatrix* matrix, const SkPaint* paint);
100    virtual void drawBitmap(SkBitmap* bitmap, float srcLeft, float srcTop,
101            float srcRight, float srcBottom, float dstLeft, float dstTop,
102            float dstRight, float dstBottom, const SkPaint* paint);
103    virtual void drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
104            const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
105            float left, float top, float right, float bottom, const SkPaint* paint);
106    virtual void drawColor(int color, SkXfermode::Mode mode);
107    virtual void drawRect(float left, float top, float right, float bottom, const SkPaint* paint);
108    virtual void drawPath(SkPath* path, SkPaint* paint);
109    virtual void drawLines(float* points, int count, const SkPaint* paint);
110    virtual void drawText(const char* text, int bytesCount, int count, float x, float y,
111            SkPaint* paint);
112
113    virtual void resetShader();
114    virtual void setupShader(SkiaShader* shader);
115
116    virtual void resetColorFilter();
117    virtual void setupColorFilter(SkiaColorFilter* filter);
118
119    virtual void resetShadow();
120    virtual void setupShadow(float radius, float dx, float dy, int color);
121
122protected:
123    /**
124     * Compose the layer defined in the current snapshot with the layer
125     * defined by the previous snapshot.
126     *
127     * The current snapshot *must* be a layer (flag kFlagIsLayer set.)
128     *
129     * @param curent The current snapshot containing the layer to compose
130     * @param previous The previous snapshot to compose the current layer with
131     */
132    virtual void composeLayer(sp<Snapshot> current, sp<Snapshot> previous);
133
134private:
135    /**
136     * Saves the current state of the renderer as a new snapshot.
137     * The new snapshot is saved in mSnapshot and the previous snapshot
138     * is linked from mSnapshot->previous.
139     *
140     * @param flags The save flags; see SkCanvas for more information
141     *
142     * @return The new save count. This value can be passed to #restoreToCount()
143     */
144    int saveSnapshot(int flags);
145
146    /**
147     * Restores the current snapshot; mSnapshot becomes mSnapshot->previous.
148     *
149     * @return True if the clip was modified.
150     */
151    bool restoreSnapshot();
152
153    /**
154     * Sets the clipping rectangle using glScissor. The clip is defined by
155     * the current snapshot's clipRect member.
156     */
157    void setScissorFromClip();
158
159    /**
160     * Creates a new layer stored in the specified snapshot.
161     *
162     * @param snapshot The snapshot associated with the new layer
163     * @param left The left coordinate of the layer
164     * @param top The top coordinate of the layer
165     * @param right The right coordinate of the layer
166     * @param bottom The bottom coordinate of the layer
167     * @param alpha The translucency of the layer
168     * @param mode The blending mode of the layer
169     * @param flags The layer save flags
170     * @param previousFbo The name of the current framebuffer
171     *
172     * @return True if the layer was successfully created, false otherwise
173     */
174    bool createLayer(sp<Snapshot> snapshot, float left, float top, float right, float bottom,
175            int alpha, SkXfermode::Mode mode, int flags, GLuint previousFbo);
176
177    /**
178     * Clears all the regions corresponding to the current list of layers.
179     * This method MUST be invoked before any drawing operation.
180     */
181    void clearLayerRegions();
182
183    /**
184     * Draws a colored rectangle with the specified color. The specified coordinates
185     * are transformed by the current snapshot's transform matrix.
186     *
187     * @param left The left coordinate of the rectangle
188     * @param top The top coordinate of the rectangle
189     * @param right The right coordinate of the rectangle
190     * @param bottom The bottom coordinate of the rectangle
191     * @param color The rectangle's ARGB color, defined as a packed 32 bits word
192     * @param mode The Skia xfermode to use
193     * @param ignoreTransform True if the current transform should be ignored
194     * @paran ignoreBlending True if the blending is set by the caller
195     */
196    void drawColorRect(float left, float top, float right, float bottom,
197            int color, SkXfermode::Mode mode, bool ignoreTransform = false);
198
199    /**
200     * Setups shaders to draw a colored rect.
201     */
202    void setupColorRect(float left, float top, float right, float bottom,
203            float r, float g, float b, float a, SkXfermode::Mode mode, bool ignoreTransform);
204
205    /**
206     * Draws a textured rectangle with the specified texture. The specified coordinates
207     * are transformed by the current snapshot's transform matrix.
208     *
209     * @param left The left coordinate of the rectangle
210     * @param top The top coordinate of the rectangle
211     * @param right The right coordinate of the rectangle
212     * @param bottom The bottom coordinate of the rectangle
213     * @param texture The texture name to map onto the rectangle
214     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
215     * @param mode The blending mode
216     * @param blend True if the texture contains an alpha channel
217     */
218    void drawTextureRect(float left, float top, float right, float bottom, GLuint texture,
219            float alpha, SkXfermode::Mode mode, bool blend);
220
221    /**
222     * Draws a textured rectangle with the specified texture. The specified coordinates
223     * are transformed by the current snapshot's transform matrix.
224     *
225     * @param left The left coordinate of the rectangle
226     * @param top The top coordinate of the rectangle
227     * @param right The right coordinate of the rectangle
228     * @param bottom The bottom coordinate of the rectangle
229     * @param texture The texture to use
230     * @param paint The paint containing the alpha, blending mode, etc.
231     */
232    void drawTextureRect(float left, float top, float right, float bottom,
233            const Texture* texture, const SkPaint* paint);
234
235    /**
236     * Draws a textured mesh with the specified texture. If the indices are omitted, the
237     * mesh is drawn as a simple quad.
238     *
239     * @param left The left coordinate of the rectangle
240     * @param top The top coordinate of the rectangle
241     * @param right The right coordinate of the rectangle
242     * @param bottom The bottom coordinate of the rectangle
243     * @param texture The texture name to map onto the rectangle
244     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
245     * @param mode The blending mode
246     * @param blend True if the texture contains an alpha channel
247     * @param vertices The vertices that define the mesh
248     * @param texCoords The texture coordinates of each vertex
249     * @param indices The indices of the vertices, can be NULL
250     * @param elementsCount The number of elements in the mesh, required by indices
251     * @param swapSrcDst Whether or not the src and dst blending operations should be swapped
252     * @param ignoreTransform True if the current transform should be ignored
253     */
254    void drawTextureMesh(float left, float top, float right, float bottom, GLuint texture,
255            float alpha, SkXfermode::Mode mode, bool blend,
256            GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
257            bool swapSrcDst = false, bool ignoreTransform = false);
258
259    /**
260     * Prepares the renderer to draw the specified shadow.
261     *
262     * @param texture The shadow texture
263     * @param x The x coordinate of the shadow
264     * @param y The y coordinate of the shadow
265     * @param mode The blending mode
266     * @param alpha The alpha value
267     */
268    void setupShadow(const ShadowTexture* texture, float x, float y, SkXfermode::Mode mode,
269            float alpha);
270
271    /**
272     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
273     *
274     * @param texture The texture to render with
275     * @param textureUnit The texture unit to use, may be modified
276     * @param x The x coordinate of the rectangle to draw
277     * @param y The y coordinate of the rectangle to draw
278     * @param r The red component of the color
279     * @param g The green component of the color
280     * @param b The blue component of the color
281     * @param a The alpha component of the color
282     * @param mode The blending mode
283     * @param transforms True if the matrix passed to the shader should be multiplied
284     *        by the model-view matrix
285     * @param applyFilters Whether or not to take color filters and
286     *        shaders into account
287     */
288    void setupTextureAlpha8(const Texture* texture, GLuint& textureUnit, float x, float y,
289            float r, float g, float b, float a, SkXfermode::Mode mode, bool transforms,
290            bool applyFilters);
291
292    /**
293     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
294     *
295     * @param texture The texture to render with
296     * @param width The width of the texture
297     * @param height The height of the texture
298     * @param textureUnit The texture unit to use, may be modified
299     * @param x The x coordinate of the rectangle to draw
300     * @param y The y coordinate of the rectangle to draw
301     * @param r The red component of the color
302     * @param g The green component of the color
303     * @param b The blue component of the color
304     * @param a The alpha component of the color
305     * @param mode The blending mode
306     * @param transforms True if the matrix passed to the shader should be multiplied
307     *        by the model-view matrix
308     * @param applyFilters Whether or not to take color filters and
309     *        shaders into account
310     */
311    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
312            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
313            SkXfermode::Mode mode, bool transforms, bool applyFilters);
314
315    /**
316     * Same as above setupTextureAlpha8() but specifies the mesh's vertices
317     * and texCoords pointers.
318     */
319    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
320            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
321            SkXfermode::Mode mode, bool transforms, bool applyFilters,
322            GLvoid* vertices, GLvoid* texCoords);
323
324    /**
325     * Draws text underline and strike-through if needed.
326     *
327     * @param text The text to decor
328     * @param bytesCount The number of bytes in the text
329     * @param length The length in pixels of the text, can be <= 0.0f to force a measurement
330     * @param x The x coordinate where the text will be drawn
331     * @param y The y coordinate where the text will be drawn
332     * @param paint The paint to draw the text with
333     */
334    void drawTextDecorations(const char* text, int bytesCount, float length,
335            float x, float y, SkPaint* paint);
336
337    /**
338     * Resets the texture coordinates stored in mMeshVertices. Setting the values
339     * back to default is achieved by calling:
340     *
341     * resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
342     *
343     * @param u1 The left coordinate of the texture
344     * @param v1 The bottom coordinate of the texture
345     * @param u2 The right coordinate of the texture
346     * @param v2 The top coordinate of the texture
347     */
348    void resetDrawTextureTexCoords(float u1, float v1, float u2, float v2);
349
350    /**
351     * Gets the alpha and xfermode out of a paint object. If the paint is null
352     * alpha will be 255 and the xfermode will be SRC_OVER.
353     *
354     * @param paint The paint to extract values from
355     * @param alpha Where to store the resulting alpha
356     * @param mode Where to store the resulting xfermode
357     */
358    inline void getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode);
359
360    /**
361     * Binds the specified texture with the specified wrap modes.
362     */
363    inline void bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit = 0);
364
365    /**
366     * Enable or disable blending as necessary. This function sets the appropriate
367     * blend function based on the specified xfermode.
368     */
369    inline void chooseBlending(bool blend, SkXfermode::Mode mode, ProgramDescription& description,
370            bool swapSrcDst = false);
371
372    /**
373     * Safely retrieves the mode from the specified xfermode. If the specified
374     * xfermode is null, the mode is assumed to be SkXfermode::kSrcOver_Mode.
375     */
376    inline SkXfermode::Mode getXfermode(SkXfermode* mode);
377
378    /**
379     * Use the specified program with the current GL context. If the program is already
380     * in use, it will not be bound again. If it is not in use, the current program is
381     * marked unused and the specified program becomes used and becomes the new
382     * current program.
383     *
384     * @param program The program to use
385     *
386     * @return true If the specified program was already in use, false otherwise.
387     */
388    inline bool useProgram(Program* program);
389
390    // Dimensions of the drawing surface
391    int mWidth, mHeight;
392
393    // Matrix used for ortho projection in shaders
394    mat4 mOrthoMatrix;
395
396    // Model-view matrix used to position/size objects
397    mat4 mModelView;
398
399    // Number of saved states
400    int mSaveCount;
401    // Base state
402    sp<Snapshot> mFirstSnapshot;
403    // Current state
404    sp<Snapshot> mSnapshot;
405
406    // Shaders
407    SkiaShader* mShader;
408
409    // Color filters
410    SkiaColorFilter* mColorFilter;
411
412    // Used to draw textured quads
413    TextureVertex mMeshVertices[4];
414
415    // GL extensions
416    Extensions mExtensions;
417
418    // Drop shadow
419    bool mHasShadow;
420    float mShadowRadius;
421    float mShadowDx;
422    float mShadowDy;
423    int mShadowColor;
424
425    // Various caches
426    Caches& mCaches;
427
428    // List of rectangles to clear due to calls to saveLayer()
429    Vector<Rect*> mLayers;
430
431    // Misc
432    GLint mMaxTextureSize;
433
434    friend class DisplayListRenderer;
435
436}; // class OpenGLRenderer
437
438}; // namespace uirenderer
439}; // namespace android
440
441#endif // ANDROID_UI_OPENGL_RENDERER_H
442