OpenGLRenderer.cpp revision 7ae7ac48aa2b53453c9805075171ecd5bcafd7de 
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#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <utils/Errors.h>
24#include <utils/KeyedVector.h>
25#include <utils/Log.h>
26
27#include <GLES2/gl2.h>
28#include <GLES2/gl2ext.h>
29
30#include <SkPaint.h>
31#include <SkXfermode.h>
32
33#include "OpenGLRenderer.h"
34#include "Matrix.h"
35
36namespace android {
37namespace uirenderer {
38
39///////////////////////////////////////////////////////////////////////////////
40// Defines
41///////////////////////////////////////////////////////////////////////////////
42
43#define V(x, y) { { x, y } }
44
45///////////////////////////////////////////////////////////////////////////////
46// Globals
47///////////////////////////////////////////////////////////////////////////////
48
49const SimpleVertex gDrawColorVertices[] = {
50        V(0.0f, 0.0f),
51        V(1.0f, 0.0f),
52        V(0.0f, 1.0f),
53        V(1.0f, 1.0f)
54};
55const GLsizei gDrawColorVertexStride = sizeof(SimpleVertex);
56const GLsizei gDrawColorVertexCount = 4;
57
58///////////////////////////////////////////////////////////////////////////////
59// Shaders
60///////////////////////////////////////////////////////////////////////////////
61
62#define SHADER_SOURCE(name, source) const char* name = #source
63
64#include "shaders/drawColor.vert"
65#include "shaders/drawColor.frag"
66
67Program::Program(const char* vertex, const char* fragment) {
68    vertexShader = buildShader(vertex, GL_VERTEX_SHADER);
69    fragmentShader = buildShader(fragment, GL_FRAGMENT_SHADER);
70
71    id = glCreateProgram();
72    glAttachShader(id, vertexShader);
73    glAttachShader(id, fragmentShader);
74    glLinkProgram(id);
75
76    GLint status;
77    glGetProgramiv(id, GL_LINK_STATUS, &status);
78    if (status != GL_TRUE) {
79        GLint infoLen = 0;
80        glGetProgramiv(id, GL_INFO_LOG_LENGTH, &infoLen);
81        if (infoLen > 1) {
82            char* log = (char*) malloc(sizeof(char) * infoLen);
83            glGetProgramInfoLog(id, infoLen, 0, log);
84            LOGE("Error while linking shaders: %s", log);
85            delete log;
86        }
87        glDeleteProgram(id);
88    }
89}
90
91Program::~Program() {
92    glDeleteShader(vertexShader);
93    glDeleteShader(fragmentShader);
94    glDeleteProgram(id);
95}
96
97void Program::use() {
98    glUseProgram(id);
99}
100
101int Program::addAttrib(const char* name) {
102    int slot = glGetAttribLocation(id, name);
103    attributes.add(name, slot);
104    return slot;
105}
106
107int Program::getAttrib(const char* name) {
108    return attributes.valueFor(name);
109}
110
111int Program::addUniform(const char* name) {
112    int slot = glGetUniformLocation(id, name);
113    uniforms.add(name, slot);
114    return slot;
115}
116
117int Program::getUniform(const char* name) {
118    return uniforms.valueFor(name);
119}
120
121GLuint Program::buildShader(const char* source, GLenum type) {
122    GLuint shader = glCreateShader(type);
123    glShaderSource(shader, 1, &source, 0);
124    glCompileShader(shader);
125
126    GLint status;
127    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
128    if (status != GL_TRUE) {
129        // Some drivers return wrong values for GL_INFO_LOG_LENGTH
130        // use a fixed size instead
131        GLchar log[512];
132        glGetShaderInfoLog(shader, sizeof(log), 0, &log[0]);
133        LOGE("Error while compiling shader: %s", log);
134        glDeleteShader(shader);
135    }
136
137    return shader;
138}
139
140DrawColorProgram::DrawColorProgram():
141        Program(gDrawColorVertexShader, gDrawColorFragmentShader) {
142    position = addAttrib("position");
143    color = addAttrib("color");
144    projection = addUniform("projection");
145    modelView = addUniform("modelView");
146    transform = addUniform("transform");
147}
148
149void DrawColorProgram::use(const GLfloat* projectionMatrix, const GLfloat* modelViewMatrix,
150        const GLfloat* transformMatrix) {
151    Program::use();
152    glUniformMatrix4fv(projection, 1, GL_FALSE, projectionMatrix);
153    glUniformMatrix4fv(modelView, 1, GL_FALSE, modelViewMatrix);
154    glUniformMatrix4fv(transform, 1, GL_FALSE, transformMatrix);
155}
156
157///////////////////////////////////////////////////////////////////////////////
158// Support
159///////////////////////////////////////////////////////////////////////////////
160
161const Rect& Snapshot::getMappedClip() {
162    if (flags & kFlagDirtyTransform) {
163        flags &= ~kFlagDirtyTransform;
164        mappedClip.set(clipRect);
165        transform.mapRect(mappedClip);
166    }
167    return mappedClip;
168}
169
170///////////////////////////////////////////////////////////////////////////////
171// Constructors/destructor
172///////////////////////////////////////////////////////////////////////////////
173
174OpenGLRenderer::OpenGLRenderer() {
175    LOGD("Create OpenGLRenderer");
176
177    mDrawColorShader = new DrawColorProgram;
178}
179
180OpenGLRenderer::~OpenGLRenderer() {
181    LOGD("Destroy OpenGLRenderer");
182}
183
184///////////////////////////////////////////////////////////////////////////////
185// Setup
186///////////////////////////////////////////////////////////////////////////////
187
188void OpenGLRenderer::setViewport(int width, int height) {
189    glViewport(0, 0, width, height);
190
191    mat4 ortho;
192    ortho.loadOrtho(0, width, height, 0, -1, 1);
193    ortho.copyTo(mOrthoMatrix);
194
195    mWidth = width;
196    mHeight = height;
197}
198
199void OpenGLRenderer::prepare() {
200    mSnapshot = &mFirstSnapshot;
201    mSaveCount = 0;
202
203    glDisable(GL_SCISSOR_TEST);
204
205    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
206    glClear(GL_COLOR_BUFFER_BIT);
207
208    glEnable(GL_SCISSOR_TEST);
209    glScissor(0, 0, mWidth, mHeight);
210
211    mSnapshot->clipRect.set(0.0f, 0.0f, mWidth, mHeight);
212}
213
214///////////////////////////////////////////////////////////////////////////////
215// State management
216///////////////////////////////////////////////////////////////////////////////
217
218int OpenGLRenderer::getSaveCount() const {
219    return mSaveCount;
220}
221
222int OpenGLRenderer::save(int flags) {
223    return saveSnapshot();
224}
225
226void OpenGLRenderer::restore() {
227    if (mSaveCount == 0) return;
228
229    if (restoreSnapshot()) {
230        setScissorFromClip();
231    }
232}
233
234void OpenGLRenderer::restoreToCount(int saveCount) {
235    if (saveCount <= 0 || saveCount > mSaveCount) return;
236
237    bool restoreClip = false;
238
239    while (mSaveCount != saveCount - 1) {
240        restoreClip |= restoreSnapshot();
241    }
242
243    if (restoreClip) {
244        setScissorFromClip();
245    }
246}
247
248int OpenGLRenderer::saveSnapshot() {
249    mSnapshot = new Snapshot(mSnapshot);
250    return ++mSaveCount;
251}
252
253bool OpenGLRenderer::restoreSnapshot() {
254    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
255
256    mSaveCount--;
257
258    // Do not merge these two lines!
259    sp<Snapshot> previous = mSnapshot->previous;
260    mSnapshot = previous;
261
262    return restoreClip;
263}
264
265///////////////////////////////////////////////////////////////////////////////
266// Transforms
267///////////////////////////////////////////////////////////////////////////////
268
269void OpenGLRenderer::translate(float dx, float dy) {
270    mSnapshot->transform.translate(dx, dy, 0.0f);
271    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
272}
273
274void OpenGLRenderer::rotate(float degrees) {
275    mSnapshot->transform.rotate(degrees, 0.0f, 0.0f, 1.0f);
276    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
277}
278
279void OpenGLRenderer::scale(float sx, float sy) {
280    mSnapshot->transform.scale(sx, sy, 1.0f);
281    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
282}
283
284void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
285    mSnapshot->transform.load(*matrix);
286    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
287}
288
289void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
290    mSnapshot->transform.copyTo(*matrix);
291}
292
293void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
294    mat4 m(*matrix);
295    mSnapshot->transform.multiply(m);
296    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
297}
298
299///////////////////////////////////////////////////////////////////////////////
300// Clipping
301///////////////////////////////////////////////////////////////////////////////
302
303void OpenGLRenderer::setScissorFromClip() {
304    const Rect& clip = mSnapshot->getMappedClip();
305    glScissor(clip.left, mHeight - clip.bottom, clip.getWidth(), clip.getHeight());
306}
307
308const Rect& OpenGLRenderer::getClipBounds() {
309    return mSnapshot->clipRect;
310}
311
312bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
313    /*
314     * The documentation of quickReject() indicates that the specified rect
315     * is transformed before being compared to the clip rect. However, the
316     * clip rect is not stored transformed in the snapshot and can thus be
317     * compared directly
318     *
319     * The following code can be used instead to performed a mapped comparison:
320     *
321     *     mSnapshot->transform.mapRect(r);
322     *     const Rect& clip = mSnapshot->getMappedClip();
323     *     return !clip.intersects(r);
324     */
325
326    Rect r(left, top, right, bottom);
327    return !mSnapshot->clipRect.intersects(r);
328}
329
330bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom) {
331    bool clipped = mSnapshot->clipRect.intersect(left, top, right, bottom);
332    if (clipped) {
333        mSnapshot->flags |= Snapshot::kFlagClipSet;
334        setScissorFromClip();
335    }
336    return clipped;
337}
338
339///////////////////////////////////////////////////////////////////////////////
340// Drawing
341///////////////////////////////////////////////////////////////////////////////
342
343void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
344    // TODO: Set the transfer mode
345    const Rect& clip = mSnapshot->clipRect;
346    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color);
347}
348
349void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* paint) {
350    // TODO Support more than  just color
351    // TODO: Set the transfer mode
352    drawColorRect(left, top, right, bottom, paint->getColor());
353}
354
355void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom, int color) {
356    GLfloat a = ((color >> 24) & 0xFF) / 255.0f;
357    GLfloat r = ((color >> 16) & 0xFF) / 255.0f;
358    GLfloat g = ((color >>  8) & 0xFF) / 255.0f;
359    GLfloat b = ((color      ) & 0xFF) / 255.0f;
360
361    mModelView.loadTranslate(left, top, 0.0f);
362    mModelView.scale(right - left, bottom - top, 1.0f);
363
364    mDrawColorShader->use(&mOrthoMatrix[0], &mModelView.data[0], &mSnapshot->transform.data[0]);
365
366    const GLvoid* p = &gDrawColorVertices[0].position[0];
367
368    glEnableVertexAttribArray(mDrawColorShader->position);
369    glVertexAttribPointer(mDrawColorShader->position, 2, GL_FLOAT, GL_FALSE,
370            gDrawColorVertexStride, p);
371    glVertexAttrib4f(mDrawColorShader->color, r, g, b, a);
372
373    glDrawArrays(GL_TRIANGLE_STRIP, 0, gDrawColorVertexCount);
374
375    glDisableVertexAttribArray(mDrawColorShader->position);
376}
377
378}; // namespace uirenderer
379}; // namespace android
380