1 /*
2 * Copyright (C) 2017 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 #include "RenderBase.h"
18 #include "glError.h"
19
20 #include <log/log.h>
21 #include <ui/GraphicBuffer.h>
22
23 // Eventually we shouldn't need this dependency, but for now the
24 // graphics allocator interface isn't fully supported on all platforms
25 // and this is our work around.
26 using ::android::GraphicBuffer;
27
28
29 // OpenGL state shared among all renderers
30 EGLDisplay RenderBase::sDisplay = EGL_NO_DISPLAY;
31 EGLContext RenderBase::sContext = EGL_NO_CONTEXT;
32 EGLSurface RenderBase::sDummySurface = EGL_NO_SURFACE;
33 GLuint RenderBase::sFrameBuffer = -1;
34 GLuint RenderBase::sColorBuffer = -1;
35 GLuint RenderBase::sDepthBuffer = -1;
36 EGLImageKHR RenderBase::sKHRimage = EGL_NO_IMAGE_KHR;
37 unsigned RenderBase::sWidth = 0;
38 unsigned RenderBase::sHeight = 0;
39 float RenderBase::sAspectRatio = 0.0f;
40
41
prepareGL()42 bool RenderBase::prepareGL() {
43 // Just trivially return success if we're already prepared
44 if (sDisplay != EGL_NO_DISPLAY) {
45 return true;
46 }
47
48 // Hardcoded to RGBx output display
49 const EGLint config_attribs[] = {
50 // Tag Value
51 EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
52 EGL_RED_SIZE, 8,
53 EGL_GREEN_SIZE, 8,
54 EGL_BLUE_SIZE, 8,
55 EGL_NONE
56 };
57
58 // Select OpenGL ES v 3
59 const EGLint context_attribs[] = {EGL_CONTEXT_CLIENT_VERSION, 3, EGL_NONE};
60
61
62 // Set up our OpenGL ES context associated with the default display (though we won't be visible)
63 EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
64 if (display == EGL_NO_DISPLAY) {
65 ALOGE("Failed to get egl display");
66 return false;
67 }
68
69 EGLint major = 0;
70 EGLint minor = 0;
71 if (!eglInitialize(display, &major, &minor)) {
72 ALOGE("Failed to initialize EGL: %s", getEGLError());
73 return false;
74 } else {
75 ALOGI("Intiialized EGL at %d.%d", major, minor);
76 }
77
78
79 // Select the configuration that "best" matches our desired characteristics
80 EGLConfig egl_config;
81 EGLint num_configs;
82 if (!eglChooseConfig(display, config_attribs, &egl_config, 1, &num_configs)) {
83 ALOGE("eglChooseConfig() failed with error: %s", getEGLError());
84 return false;
85 }
86
87
88 // Create a placeholder pbuffer so we have a surface to bind -- we never intend to draw to this
89 // because attachRenderTarget will be called first.
90 EGLint surface_attribs[] = { EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE };
91 sDummySurface = eglCreatePbufferSurface(display, egl_config, surface_attribs);
92 if (sDummySurface == EGL_NO_SURFACE) {
93 ALOGE("Failed to create OpenGL ES Dummy surface: %s", getEGLError());
94 return false;
95 } else {
96 ALOGI("Dummy surface looks good! :)");
97 }
98
99
100 //
101 // Create the EGL context
102 //
103 EGLContext context = eglCreateContext(display, egl_config, EGL_NO_CONTEXT, context_attribs);
104 if (context == EGL_NO_CONTEXT) {
105 ALOGE("Failed to create OpenGL ES Context: %s", getEGLError());
106 return false;
107 }
108
109
110 // Activate our render target for drawing
111 if (!eglMakeCurrent(display, sDummySurface, sDummySurface, context)) {
112 ALOGE("Failed to make the OpenGL ES Context current: %s", getEGLError());
113 return false;
114 } else {
115 ALOGI("We made our context current! :)");
116 }
117
118
119 // Report the extensions available on this implementation
120 const char* gl_extensions = (const char*) glGetString(GL_EXTENSIONS);
121 ALOGI("GL EXTENSIONS:\n %s", gl_extensions);
122
123
124 // Reserve handles for the color and depth targets we'll be setting up
125 glGenRenderbuffers(1, &sColorBuffer);
126 glGenRenderbuffers(1, &sDepthBuffer);
127
128 // Set up the frame buffer object we can modify and use for off screen rendering
129 glGenFramebuffers(1, &sFrameBuffer);
130 glBindFramebuffer(GL_FRAMEBUFFER, sFrameBuffer);
131
132
133 // Now that we're assured success, store object handles we constructed
134 sDisplay = display;
135 sContext = context;
136
137 return true;
138 }
139
140
attachRenderTarget(const BufferDesc & tgtBuffer)141 bool RenderBase::attachRenderTarget(const BufferDesc& tgtBuffer) {
142 // Hardcoded to RGBx for now
143 if (tgtBuffer.format != HAL_PIXEL_FORMAT_RGBA_8888) {
144 ALOGE("Unsupported target buffer format");
145 return false;
146 }
147
148 // create a GraphicBuffer from the existing handle
149 sp<GraphicBuffer> pGfxBuffer = new GraphicBuffer(tgtBuffer.memHandle,
150 GraphicBuffer::CLONE_HANDLE,
151 tgtBuffer.width, tgtBuffer.height,
152 tgtBuffer.format, 1, // layer count
153 GRALLOC_USAGE_HW_RENDER,
154 tgtBuffer.stride);
155 if (pGfxBuffer.get() == nullptr) {
156 ALOGE("Failed to allocate GraphicBuffer to wrap image handle");
157 return false;
158 }
159
160 // Get a GL compatible reference to the graphics buffer we've been given
161 EGLint eglImageAttributes[] = {EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE};
162 EGLClientBuffer clientBuf = static_cast<EGLClientBuffer>(pGfxBuffer->getNativeBuffer());
163 sKHRimage = eglCreateImageKHR(sDisplay, EGL_NO_CONTEXT,
164 EGL_NATIVE_BUFFER_ANDROID, clientBuf,
165 eglImageAttributes);
166 if (sKHRimage == EGL_NO_IMAGE_KHR) {
167 ALOGE("error creating EGLImage for target buffer: %s", getEGLError());
168 return false;
169 }
170
171 // Construct a render buffer around the external buffer
172 glBindRenderbuffer(GL_RENDERBUFFER, sColorBuffer);
173 glEGLImageTargetRenderbufferStorageOES(GL_RENDERBUFFER, static_cast<GLeglImageOES>(sKHRimage));
174 if (eglGetError() != EGL_SUCCESS) {
175 ALOGI("glEGLImageTargetRenderbufferStorageOES => %s", getEGLError());
176 return false;
177 }
178
179 glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, sColorBuffer);
180 if (eglGetError() != EGL_SUCCESS) {
181 ALOGE("glFramebufferRenderbuffer => %s", getEGLError());
182 return false;
183 }
184
185 GLenum checkResult = glCheckFramebufferStatus(GL_FRAMEBUFFER);
186 if (checkResult != GL_FRAMEBUFFER_COMPLETE) {
187 ALOGE("Offscreen framebuffer not configured successfully (%d: %s)",
188 checkResult, getGLFramebufferError());
189 return false;
190 }
191
192 // Store the size of our target buffer
193 sWidth = tgtBuffer.width;
194 sHeight = tgtBuffer.height;
195 sAspectRatio = (float)sWidth / sHeight;
196
197 // Set the viewport
198 glViewport(0, 0, sWidth, sHeight);
199
200 #if 1 // We don't actually need the clear if we're going to cover the whole screen anyway
201 // Clear the color buffer
202 glClearColor(0.8f, 0.1f, 0.2f, 1.0f);
203 glClear(GL_COLOR_BUFFER_BIT);
204 #endif
205
206
207 return true;
208 }
209
210
detachRenderTarget()211 void RenderBase::detachRenderTarget() {
212 // Drop our external render target
213 if (sKHRimage != EGL_NO_IMAGE_KHR) {
214 eglDestroyImageKHR(sDisplay, sKHRimage);
215 sKHRimage = EGL_NO_IMAGE_KHR;
216 }
217 }