OpenGLRenderer.h revision 99bcdc52dcb365ed7d8cfa13540fb33fbcbbac9d 
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    const float* getMatrix() const;
91    void getMatrix(SkMatrix* matrix);
92    virtual void setMatrix(SkMatrix* matrix);
93    virtual void concatMatrix(SkMatrix* matrix);
94
95    const Rect& getClipBounds();
96    bool quickReject(float left, float top, float right, float bottom);
97    virtual bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op);
98
99    virtual void drawBitmap(SkBitmap* bitmap, float left, float top, const SkPaint* paint);
100    virtual void drawBitmap(SkBitmap* bitmap, const SkMatrix* matrix, const SkPaint* paint);
101    virtual void drawBitmap(SkBitmap* bitmap, float srcLeft, float srcTop,
102            float srcRight, float srcBottom, float dstLeft, float dstTop,
103            float dstRight, float dstBottom, const SkPaint* paint);
104    virtual void drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
105            const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
106            float left, float top, float right, float bottom, const SkPaint* paint);
107    virtual void drawColor(int color, SkXfermode::Mode mode);
108    virtual void drawRect(float left, float top, float right, float bottom, const SkPaint* paint);
109    virtual void drawPath(SkPath* path, SkPaint* paint);
110    virtual void drawLines(float* points, int count, const SkPaint* paint);
111    virtual void drawText(const char* text, int bytesCount, int count, float x, float y,
112            SkPaint* paint);
113
114    virtual void resetShader();
115    virtual void setupShader(SkiaShader* shader);
116
117    virtual void resetColorFilter();
118    virtual void setupColorFilter(SkiaColorFilter* filter);
119
120    virtual void resetShadow();
121    virtual void setupShadow(float radius, float dx, float dy, int color);
122
123protected:
124    /**
125     * Compose the layer defined in the current snapshot with the layer
126     * defined by the previous snapshot.
127     *
128     * The current snapshot *must* be a layer (flag kFlagIsLayer set.)
129     *
130     * @param curent The current snapshot containing the layer to compose
131     * @param previous The previous snapshot to compose the current layer with
132     */
133    virtual void composeLayer(sp<Snapshot> current, sp<Snapshot> previous);
134
135private:
136    /**
137     * Saves the current state of the renderer as a new snapshot.
138     * The new snapshot is saved in mSnapshot and the previous snapshot
139     * is linked from mSnapshot->previous.
140     *
141     * @param flags The save flags; see SkCanvas for more information
142     *
143     * @return The new save count. This value can be passed to #restoreToCount()
144     */
145    int saveSnapshot(int flags);
146
147    /**
148     * Restores the current snapshot; mSnapshot becomes mSnapshot->previous.
149     *
150     * @return True if the clip was modified.
151     */
152    bool restoreSnapshot();
153
154    /**
155     * Sets the clipping rectangle using glScissor. The clip is defined by
156     * the current snapshot's clipRect member.
157     */
158    void setScissorFromClip();
159
160    /**
161     * Creates a new layer stored in the specified snapshot.
162     *
163     * @param snapshot The snapshot associated with the new layer
164     * @param left The left coordinate of the layer
165     * @param top The top coordinate of the layer
166     * @param right The right coordinate of the layer
167     * @param bottom The bottom coordinate of the layer
168     * @param alpha The translucency of the layer
169     * @param mode The blending mode of the layer
170     * @param flags The layer save flags
171     * @param previousFbo The name of the current framebuffer
172     *
173     * @return True if the layer was successfully created, false otherwise
174     */
175    bool createLayer(sp<Snapshot> snapshot, float left, float top, float right, float bottom,
176            int alpha, SkXfermode::Mode mode, int flags, GLuint previousFbo);
177
178    /**
179     * Clears all the regions corresponding to the current list of layers.
180     * This method MUST be invoked before any drawing operation.
181     */
182    void clearLayerRegions();
183
184    /**
185     * Draws a colored rectangle with the specified color. The specified coordinates
186     * are transformed by the current snapshot's transform matrix.
187     *
188     * @param left The left coordinate of the rectangle
189     * @param top The top coordinate of the rectangle
190     * @param right The right coordinate of the rectangle
191     * @param bottom The bottom coordinate of the rectangle
192     * @param color The rectangle's ARGB color, defined as a packed 32 bits word
193     * @param mode The Skia xfermode to use
194     * @param ignoreTransform True if the current transform should be ignored
195     * @paran ignoreBlending True if the blending is set by the caller
196     */
197    void drawColorRect(float left, float top, float right, float bottom,
198            int color, SkXfermode::Mode mode, bool ignoreTransform = false);
199
200    /**
201     * Setups shaders to draw a colored rect.
202     */
203    void setupColorRect(float left, float top, float right, float bottom,
204            float r, float g, float b, float a, SkXfermode::Mode mode, bool ignoreTransform);
205
206    /**
207     * Draws a textured rectangle with the specified texture. The specified coordinates
208     * are transformed by the current snapshot's transform matrix.
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     */
219    void drawTextureRect(float left, float top, float right, float bottom, GLuint texture,
220            float alpha, SkXfermode::Mode mode, bool blend);
221
222    /**
223     * Draws a textured rectangle with the specified texture. The specified coordinates
224     * are transformed by the current snapshot's transform matrix.
225     *
226     * @param left The left coordinate of the rectangle
227     * @param top The top coordinate of the rectangle
228     * @param right The right coordinate of the rectangle
229     * @param bottom The bottom coordinate of the rectangle
230     * @param texture The texture to use
231     * @param paint The paint containing the alpha, blending mode, etc.
232     */
233    void drawTextureRect(float left, float top, float right, float bottom,
234            const Texture* texture, const SkPaint* paint);
235
236    /**
237     * Draws a textured mesh with the specified texture. If the indices are omitted, the
238     * mesh is drawn as a simple quad.
239     *
240     * @param left The left coordinate of the rectangle
241     * @param top The top coordinate of the rectangle
242     * @param right The right coordinate of the rectangle
243     * @param bottom The bottom coordinate of the rectangle
244     * @param texture The texture name to map onto the rectangle
245     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
246     * @param mode The blending mode
247     * @param blend True if the texture contains an alpha channel
248     * @param vertices The vertices that define the mesh
249     * @param texCoords The texture coordinates of each vertex
250     * @param indices The indices of the vertices, can be NULL
251     * @param elementsCount The number of elements in the mesh, required by indices
252     * @param swapSrcDst Whether or not the src and dst blending operations should be swapped
253     * @param ignoreTransform True if the current transform should be ignored
254     */
255    void drawTextureMesh(float left, float top, float right, float bottom, GLuint texture,
256            float alpha, SkXfermode::Mode mode, bool blend,
257            GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
258            bool swapSrcDst = false, bool ignoreTransform = false);
259
260    /**
261     * Prepares the renderer to draw the specified shadow.
262     *
263     * @param texture The shadow texture
264     * @param x The x coordinate of the shadow
265     * @param y The y coordinate of the shadow
266     * @param mode The blending mode
267     * @param alpha The alpha value
268     */
269    void setupShadow(const ShadowTexture* texture, float x, float y, SkXfermode::Mode mode,
270            float alpha);
271
272    /**
273     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
274     *
275     * @param texture The texture to render with
276     * @param textureUnit The texture unit to use, may be modified
277     * @param x The x coordinate of the rectangle to draw
278     * @param y The y coordinate of the rectangle to draw
279     * @param r The red component of the color
280     * @param g The green component of the color
281     * @param b The blue component of the color
282     * @param a The alpha component of the color
283     * @param mode The blending mode
284     * @param transforms True if the matrix passed to the shader should be multiplied
285     *        by the model-view matrix
286     * @param applyFilters Whether or not to take color filters and
287     *        shaders into account
288     */
289    void setupTextureAlpha8(const Texture* texture, GLuint& textureUnit, float x, float y,
290            float r, float g, float b, float a, SkXfermode::Mode mode, bool transforms,
291            bool applyFilters);
292
293    /**
294     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
295     *
296     * @param texture The texture to render with
297     * @param width The width of the texture
298     * @param height The height of the texture
299     * @param textureUnit The texture unit to use, may be modified
300     * @param x The x coordinate of the rectangle to draw
301     * @param y The y coordinate of the rectangle to draw
302     * @param r The red component of the color
303     * @param g The green component of the color
304     * @param b The blue component of the color
305     * @param a The alpha component of the color
306     * @param mode The blending mode
307     * @param transforms True if the matrix passed to the shader should be multiplied
308     *        by the model-view matrix
309     * @param applyFilters Whether or not to take color filters and
310     *        shaders into account
311     */
312    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
313            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
314            SkXfermode::Mode mode, bool transforms, bool applyFilters);
315
316    /**
317     * Same as above setupTextureAlpha8() but specifies the mesh's vertices
318     * and texCoords pointers.
319     */
320    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
321            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
322            SkXfermode::Mode mode, bool transforms, bool applyFilters,
323            GLvoid* vertices, GLvoid* texCoords);
324
325    /**
326     * Draws text underline and strike-through if needed.
327     *
328     * @param text The text to decor
329     * @param bytesCount The number of bytes in the text
330     * @param length The length in pixels of the text, can be <= 0.0f to force a measurement
331     * @param x The x coordinate where the text will be drawn
332     * @param y The y coordinate where the text will be drawn
333     * @param paint The paint to draw the text with
334     */
335    void drawTextDecorations(const char* text, int bytesCount, float length,
336            float x, float y, SkPaint* paint);
337
338    /**
339     * Resets the texture coordinates stored in mMeshVertices. Setting the values
340     * back to default is achieved by calling:
341     *
342     * resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
343     *
344     * @param u1 The left coordinate of the texture
345     * @param v1 The bottom coordinate of the texture
346     * @param u2 The right coordinate of the texture
347     * @param v2 The top coordinate of the texture
348     */
349    void resetDrawTextureTexCoords(float u1, float v1, float u2, float v2);
350
351    /**
352     * Gets the alpha and xfermode out of a paint object. If the paint is null
353     * alpha will be 255 and the xfermode will be SRC_OVER.
354     *
355     * @param paint The paint to extract values from
356     * @param alpha Where to store the resulting alpha
357     * @param mode Where to store the resulting xfermode
358     */
359    inline void getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode);
360
361    /**
362     * Binds the specified texture with the specified wrap modes.
363     */
364    inline void bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit = 0);
365
366    /**
367     * Enable or disable blending as necessary. This function sets the appropriate
368     * blend function based on the specified xfermode.
369     */
370    inline void chooseBlending(bool blend, SkXfermode::Mode mode, ProgramDescription& description,
371            bool swapSrcDst = false);
372
373    /**
374     * Safely retrieves the mode from the specified xfermode. If the specified
375     * xfermode is null, the mode is assumed to be SkXfermode::kSrcOver_Mode.
376     */
377    inline SkXfermode::Mode getXfermode(SkXfermode* mode);
378
379    /**
380     * Use the specified program with the current GL context. If the program is already
381     * in use, it will not be bound again. If it is not in use, the current program is
382     * marked unused and the specified program becomes used and becomes the new
383     * current program.
384     *
385     * @param program The program to use
386     *
387     * @return true If the specified program was already in use, false otherwise.
388     */
389    inline bool useProgram(Program* program);
390
391    // Dimensions of the drawing surface
392    int mWidth, mHeight;
393
394    // Matrix used for ortho projection in shaders
395    mat4 mOrthoMatrix;
396
397    // Model-view matrix used to position/size objects
398    mat4 mModelView;
399
400    // Number of saved states
401    int mSaveCount;
402    // Base state
403    sp<Snapshot> mFirstSnapshot;
404    // Current state
405    sp<Snapshot> mSnapshot;
406
407    // Shaders
408    SkiaShader* mShader;
409
410    // Color filters
411    SkiaColorFilter* mColorFilter;
412
413    // Used to draw textured quads
414    TextureVertex mMeshVertices[4];
415
416    // GL extensions
417    Extensions mExtensions;
418
419    // Drop shadow
420    bool mHasShadow;
421    float mShadowRadius;
422    float mShadowDx;
423    float mShadowDy;
424    int mShadowColor;
425
426    // Various caches
427    Caches& mCaches;
428
429    // List of rectangles to clear due to calls to saveLayer()
430    Vector<Rect*> mLayers;
431
432    // Misc
433    GLint mMaxTextureSize;
434
435    // Indentity matrix
436    const mat4 mIdentity;
437
438    friend class DisplayListRenderer;
439
440}; // class OpenGLRenderer
441
442}; // namespace uirenderer
443}; // namespace android
444
445#endif // ANDROID_UI_OPENGL_RENDERER_H
446