OpenGLRenderer.h revision 0a41749953f35d33f61b3119e3161a82bb5fa59e 
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 should be also reapplied by calling
124     *         #setScissorFromClip().
125     */
126    bool restoreSnapshot();
127
128    /**
129     * Sets the clipping rectangle using glScissor. The clip is defined by
130     * the current snapshot's clipRect member.
131     */
132    void setScissorFromClip();
133
134    /**
135     * Compose the layer defined in the current snapshot with the layer
136     * defined by the previous snapshot.
137     *
138     * The current snapshot *must* be a layer (flag kFlagIsLayer set.)
139     *
140     * @param curent The current snapshot containing the layer to compose
141     * @param previous The previous snapshot to compose the current layer with
142     */
143    void composeLayer(sp<Snapshot> current, sp<Snapshot> previous);
144
145    /**
146     * Creates a new layer stored in the specified snapshot.
147     *
148     * @param snapshot The snapshot associated with the new layer
149     * @param left The left coordinate of the layer
150     * @param top The top coordinate of the layer
151     * @param right The right coordinate of the layer
152     * @param bottom The bottom coordinate of the layer
153     * @param alpha The translucency of the layer
154     * @param mode The blending mode of the layer
155     * @param flags The layer save flags
156     *
157     * @return True if the layer was successfully created, false otherwise
158     */
159    bool createLayer(sp<Snapshot> snapshot, float left, float top, float right, float bottom,
160            int alpha, SkXfermode::Mode mode, int flags);
161
162    /**
163     * Draws a colored rectangle with the specified color. The specified coordinates
164     * are transformed by the current snapshot's transform matrix.
165     *
166     * @param left The left coordinate of the rectangle
167     * @param top The top coordinate of the rectangle
168     * @param right The right coordinate of the rectangle
169     * @param bottom The bottom coordinate of the rectangle
170     * @param color The rectangle's ARGB color, defined as a packed 32 bits word
171     * @param mode The Skia xfermode to use
172     * @param ignoreTransform True if the current transform should be ignored
173     */
174    void drawColorRect(float left, float top, float right, float bottom,
175    		int color, SkXfermode::Mode mode, bool ignoreTransform = false);
176
177    /**
178     * Draws a textured rectangle with the specified texture. The specified coordinates
179     * are transformed by the current snapshot's transform matrix.
180     *
181     * @param left The left coordinate of the rectangle
182     * @param top The top coordinate of the rectangle
183     * @param right The right coordinate of the rectangle
184     * @param bottom The bottom coordinate of the rectangle
185     * @param texture The texture name to map onto the rectangle
186     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
187     * @param mode The blending mode
188     * @param blend True if the texture contains an alpha channel
189     */
190    void drawTextureRect(float left, float top, float right, float bottom, GLuint texture,
191            float alpha, SkXfermode::Mode mode, bool blend);
192
193    /**
194     * Draws a textured rectangle with the specified texture. The specified coordinates
195     * are transformed by the current snapshot's transform matrix.
196     *
197     * @param left The left coordinate of the rectangle
198     * @param top The top coordinate of the rectangle
199     * @param right The right coordinate of the rectangle
200     * @param bottom The bottom coordinate of the rectangle
201     * @param texture The texture to use
202     * @param paint The paint containing the alpha, blending mode, etc.
203     */
204    void drawTextureRect(float left, float top, float right, float bottom,
205            const Texture* texture, const SkPaint* paint);
206
207    /**
208     * Draws a textured mesh with the specified texture. If the indices are omitted, the
209     * mesh is drawn as a simple quad.
210     *
211     * @param left The left coordinate of the rectangle
212     * @param top The top coordinate of the rectangle
213     * @param right The right coordinate of the rectangle
214     * @param bottom The bottom coordinate of the rectangle
215     * @param texture The texture name to map onto the rectangle
216     * @param alpha An additional translucency parameter, between 0.0f and 1.0f
217     * @param mode The blending mode
218     * @param blend True if the texture contains an alpha channel
219     * @param vertices The vertices that define the mesh
220     * @param texCoords The texture coordinates of each vertex
221     * @param indices The indices of the vertices, can be NULL
222     * @param elementsCount The number of elements in the mesh, required by indices
223     */
224    void drawTextureMesh(float left, float top, float right, float bottom, GLuint texture,
225            float alpha, SkXfermode::Mode mode, bool blend,
226            GLvoid* vertices, GLvoid* texCoords, GLvoid* indices, GLsizei elementsCount = 0);
227
228    /**
229     * Prepares the renderer to draw the specified shadow.
230     *
231     * @param texture The shadow texture
232     * @param x The x coordinate of the shadow
233     * @param y The y coordinate of the shadow
234     * @param mode The blending mode
235     */
236    void setupShadow(const ShadowTexture* texture, float x, float y, SkXfermode::Mode mode);
237
238    /**
239     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
240     *
241     * @param texture The texture to render with
242     * @param textureUnit The texture unit to use, may be modified
243     * @param x The x coordinate of the rectangle to draw
244     * @param y The y coordinate of the rectangle to draw
245     * @param r The red component of the color
246     * @param g The green component of the color
247     * @param b The blue component of the color
248     * @param a The alpha component of the color
249     * @param mode The blending mode
250     * @param transforms True if the matrix passed to the shader should be multiplied
251     *        by the model-view matrix
252     * @param applyFilters Whether or not to take color filters and
253     *        shaders into account
254     */
255    void setupTextureAlpha8(const Texture* texture, GLuint& textureUnit, float x, float y,
256            float r, float g, float b, float a, SkXfermode::Mode mode, bool transforms,
257            bool applyFilters);
258
259    /**
260     * Prepares the renderer to draw the specified Alpha8 texture as a rectangle.
261     *
262     * @param texture The texture to render with
263     * @param width The width of the texture
264     * @param height The height of the texture
265     * @param textureUnit The texture unit to use, may be modified
266     * @param x The x coordinate of the rectangle to draw
267     * @param y The y coordinate of the rectangle to draw
268     * @param r The red component of the color
269     * @param g The green component of the color
270     * @param b The blue component of the color
271     * @param a The alpha component of the color
272     * @param mode The blending mode
273     * @param transforms True if the matrix passed to the shader should be multiplied
274     *        by the model-view matrix
275     * @param applyFilters Whether or not to take color filters and
276     *        shaders into account
277     */
278    void setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
279            GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
280            SkXfermode::Mode mode, bool transforms, bool applyFilters);
281
282    /**
283     * Draws text underline and strike-through if needed.
284     *
285     * @param text The text to decor
286     * @param bytesCount The number of bytes in the text
287     * @param length The length in pixels of the text, can be <= 0.0f to force a measurement
288     * @param x The x coordinate where the text will be drawn
289     * @param y The y coordinate where the text will be drawn
290     * @param paint The paint to draw the text with
291     */
292    void drawTextDecorations(const char* text, int bytesCount, float length,
293            float x, float y, SkPaint* paint);
294
295    /**
296     * Resets the texture coordinates stored in mMeshVertices. Setting the values
297     * back to default is achieved by calling:
298     *
299     * resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
300     *
301     * @param u1 The left coordinate of the texture
302     * @param v1 The bottom coordinate of the texture
303     * @param u2 The right coordinate of the texture
304     * @param v2 The top coordinate of the texture
305     */
306    void resetDrawTextureTexCoords(float u1, float v1, float u2, float v2);
307
308    /**
309     * Gets the alpha and xfermode out of a paint object. If the paint is null
310     * alpha will be 255 and the xfermode will be SRC_OVER.
311     *
312     * @param paint The paint to extract values from
313     * @param alpha Where to store the resulting alpha
314     * @param mode Where to store the resulting xfermode
315     */
316    inline void getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode);
317
318    /**
319     * Binds the specified texture with the specified wrap modes.
320     */
321    inline void bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit = 0);
322
323    /**
324     * Enable or disable blending as necessary. This function sets the appropriate
325     * blend function based on the specified xfermode.
326     */
327    inline void chooseBlending(bool blend, SkXfermode::Mode mode, bool isPremultiplied = true);
328
329    /**
330     * Use the specified program with the current GL context. If the program is already
331     * in use, it will not be bound again. If it is not in use, the current program is
332     * marked unused and the specified program becomes used and becomes the new
333     * current program.
334     *
335     * @param program The program to use
336     *
337     * @return true If the specified program was already in use, false otherwise.
338     */
339    inline bool useProgram(Program* program);
340
341    // Dimensions of the drawing surface
342    int mWidth, mHeight;
343
344    // Matrix used for ortho projection in shaders
345    mat4 mOrthoMatrix;
346
347    // Model-view matrix used to position/size objects
348    mat4 mModelView;
349
350    // Number of saved states
351    int mSaveCount;
352    // Base state
353    sp<Snapshot> mFirstSnapshot;
354    // Current state
355    sp<Snapshot> mSnapshot;
356
357    // Shaders
358    Program* mCurrentProgram;
359    SkiaShader* mShader;
360
361    // Color filters
362    SkiaColorFilter* mColorFilter;
363
364    // Used to draw textured quads
365    TextureVertex mMeshVertices[4];
366
367    // Last known blend state
368    bool mBlend;
369    GLenum mLastSrcMode;
370    GLenum mLastDstMode;
371
372    // GL extensions
373    Extensions mExtensions;
374
375    // Font renderer
376    FontRenderer mFontRenderer;
377
378    // Drop shadow
379    bool mHasShadow;
380    float mShadowRadius;
381    float mShadowDx;
382    float mShadowDy;
383    int mShadowColor;
384
385    // Various caches
386    TextureCache mTextureCache;
387    LayerCache mLayerCache;
388    GradientCache mGradientCache;
389    ProgramCache mProgramCache;
390    PathCache mPathCache;
391    PatchCache mPatchCache;
392    TextDropShadowCache mDropShadowCache;
393}; // class OpenGLRenderer
394
395}; // namespace uirenderer
396}; // namespace android
397
398#endif // ANDROID_UI_OPENGL_RENDERER_H
399