gl2_basic.cpp revision 18e24f952506beebe1eea5672a7dbf60c1040556 
1/*
2 * Copyright (C) 2007 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 <stdlib.h>
18#include <stdio.h>
19#include <time.h>
20#include <sched.h>
21#include <sys/resource.h>
22
23#include <EGL/egl.h>
24#include <GLES2/gl2.h>
25#include <GLES2/gl2ext.h>
26
27#include <utils/Timers.h>
28
29#include <ui/FramebufferNativeWindow.h>
30#include <ui/EGLUtils.h>
31
32using namespace android;
33
34static void printGLString(const char *name, GLenum s) {
35    // fprintf(stderr, "printGLString %s, %d\n", name, s);
36    const char *v = (const char *) glGetString(s);
37    // int error = glGetError();
38    // fprintf(stderr, "glGetError() = %d, result of glGetString = %x\n", error,
39    //        (unsigned int) v);
40    // if ((v < (const char*) 0) || (v > (const char*) 0x10000))
41    //    fprintf(stderr, "GL %s = %s\n", name, v);
42    // else
43    //    fprintf(stderr, "GL %s = (null) 0x%08x\n", name, (unsigned int) v);
44    fprintf(stderr, "GL %s = %s\n", name, v);
45}
46
47static void checkEglError(const char* op, EGLBoolean returnVal = EGL_TRUE) {
48    if (returnVal != EGL_TRUE) {
49        fprintf(stderr, "%s() returned %d\n", op, returnVal);
50    }
51
52    for (EGLint error = eglGetError(); error != EGL_SUCCESS; error
53            = eglGetError()) {
54        fprintf(stderr, "after %s() eglError %s (0x%x)\n", op, EGLUtils::strerror(error),
55                error);
56    }
57}
58
59static void checkGlError(const char* op) {
60    for (GLint error = glGetError(); error; error
61            = glGetError()) {
62        fprintf(stderr, "after %s() glError (0x%x)\n", op, error);
63    }
64}
65
66static const char gVertexShader[] = "attribute vec4 vPosition;\n"
67    "void main() {\n"
68    "  gl_Position = vPosition;\n"
69    "}\n";
70
71static const char gFragmentShader[] = "precision mediump float;\n"
72    "void main() {\n"
73    "  gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);\n"
74    "}\n";
75
76GLuint loadShader(GLenum shaderType, const char* pSource) {
77    GLuint shader = glCreateShader(shaderType);
78    if (shader) {
79        glShaderSource(shader, 1, &pSource, NULL);
80        glCompileShader(shader);
81        GLint compiled = 0;
82        glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled);
83        if (!compiled) {
84            GLint infoLen = 0;
85            glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLen);
86            if (infoLen) {
87                char* buf = (char*) malloc(infoLen);
88                if (buf) {
89                    glGetShaderInfoLog(shader, infoLen, NULL, buf);
90                    fprintf(stderr, "Could not compile shader %d:\n%s\n",
91                            shaderType, buf);
92                    free(buf);
93                }
94                glDeleteShader(shader);
95                shader = 0;
96            }
97        }
98    }
99    return shader;
100}
101
102GLuint createProgram(const char* pVertexSource, const char* pFragmentSource) {
103    GLuint vertexShader = loadShader(GL_VERTEX_SHADER, pVertexSource);
104    if (!vertexShader) {
105        return 0;
106    }
107
108    GLuint pixelShader = loadShader(GL_FRAGMENT_SHADER, pFragmentSource);
109    if (!pixelShader) {
110        return 0;
111    }
112
113    GLuint program = glCreateProgram();
114    if (program) {
115        glAttachShader(program, vertexShader);
116        checkGlError("glAttachShader");
117        glAttachShader(program, pixelShader);
118        checkGlError("glAttachShader");
119        glLinkProgram(program);
120        GLint linkStatus = GL_FALSE;
121        glGetProgramiv(program, GL_LINK_STATUS, &linkStatus);
122        if (linkStatus != GL_TRUE) {
123            GLint bufLength = 0;
124            glGetProgramiv(program, GL_INFO_LOG_LENGTH, &bufLength);
125            if (bufLength) {
126                char* buf = (char*) malloc(bufLength);
127                if (buf) {
128                    glGetProgramInfoLog(program, bufLength, NULL, buf);
129                    fprintf(stderr, "Could not link program:\n%s\n", buf);
130                    free(buf);
131                }
132            }
133            glDeleteProgram(program);
134            program = 0;
135        }
136    }
137    return program;
138}
139
140GLuint gProgram;
141GLuint gvPositionHandle;
142
143bool setupGraphics(int w, int h) {
144    gProgram = createProgram(gVertexShader, gFragmentShader);
145    if (!gProgram) {
146        return false;
147    }
148    gvPositionHandle = glGetAttribLocation(gProgram, "vPosition");
149    checkGlError("glGetAttribLocation");
150    fprintf(stderr, "glGetAttribLocation(\"vPosition\") = %d\n",
151            gvPositionHandle);
152
153    glViewport(0, 0, w, h);
154    checkGlError("glViewport");
155    return true;
156}
157
158const GLfloat gTriangleVertices[] = { 0.0f, 0.5f, -0.5f, -0.5f,
159        0.5f, -0.5f };
160
161void renderFrame() {
162    glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
163    checkGlError("glClearColor");
164    glClear( GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
165    checkGlError("glClear");
166
167    glUseProgram(gProgram);
168    checkGlError("glUseProgram");
169
170    glVertexAttribPointer(gvPositionHandle, 2, GL_FLOAT, GL_FALSE, 0, gTriangleVertices);
171    checkGlError("glVertexAttribPointer");
172    glEnableVertexAttribArray(gvPositionHandle);
173    checkGlError("glEnableVertexAttribArray");
174    glDrawArrays(GL_TRIANGLES, 0, 3);
175    checkGlError("glDrawArrays");
176}
177
178#if 0
179
180void PrintEGLConfig(EGLDisplay dpy, EGLConfig config) {
181	int attrib[] = {EGL_RED_SIZE, EGL_GREEN_SIZE, EGL_BLUE_SIZE, EGL_ALPHA_SIZE,
182			EGL_DEPTH_SIZE, EGL_SURFACE_TYPE, EGL_RENDERABLE_TYPE
183	};
184	for(size_t i = 0; i < sizeof(attrib)/sizeof(attrib[0]); i++) {
185        int value = 0;
186        int a = attrib[i];
187        if (eglGetConfigAttrib(dpy, config, a, &value)) {
188            printf(" 0x%04x: %d", a, value);
189        }
190	}
191	printf("\n");
192}
193
194#endif
195
196int main(int argc, char** argv) {
197    EGLBoolean returnValue;
198    EGLConfig myConfig = {0};
199
200    EGLint context_attribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
201    EGLint s_configAttribs[] = {
202            EGL_SURFACE_TYPE, EGL_PBUFFER_BIT|EGL_WINDOW_BIT,
203            EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
204            EGL_NONE };
205    EGLint majorVersion;
206    EGLint minorVersion;
207    EGLContext context;
208    EGLSurface surface;
209    EGLint w, h;
210
211    EGLDisplay dpy;
212
213    checkEglError("<init>");
214    dpy = eglGetDisplay(EGL_DEFAULT_DISPLAY);
215    checkEglError("eglGetDisplay");
216    if (dpy == EGL_NO_DISPLAY) {
217        printf("eglGetDisplay returned EGL_NO_DISPLAY.\n");
218        return 0;
219    }
220
221    returnValue = eglInitialize(dpy, &majorVersion, &minorVersion);
222    checkEglError("eglInitialize", returnValue);
223    fprintf(stderr, "EGL version %d.%d\n", majorVersion, minorVersion);
224    if (returnValue != EGL_TRUE) {
225        printf("eglInitialize failed\n");
226        return 0;
227    }
228
229    EGLNativeWindowType window = android_createDisplaySurface();
230    returnValue = EGLUtils::selectConfigForNativeWindow(dpy, s_configAttribs, window, &myConfig);
231    if (returnValue) {
232    	printf("EGLUtils::selectConfigForNativeWindow() returned %d", returnValue);
233    	return 0;
234    }
235
236    surface = eglCreateWindowSurface(dpy, myConfig, window, NULL);
237    checkEglError("eglCreateWindowSurface");
238    if (surface == EGL_NO_SURFACE) {
239        printf("gelCreateWindowSurface failed.\n");
240        return 0;
241    }
242
243    context = eglCreateContext(dpy, myConfig, EGL_NO_CONTEXT, context_attribs);
244    checkEglError("eglCreateContext");
245    if (context == EGL_NO_CONTEXT) {
246        printf("eglCreateContext failed\n");
247        return 0;
248    }
249    returnValue = eglMakeCurrent(dpy, surface, surface, context);
250    checkEglError("eglMakeCurrent", returnValue);
251    if (returnValue != EGL_TRUE) {
252        return 0;
253    }
254    eglQuerySurface(dpy, surface, EGL_WIDTH, &w);
255    checkEglError("eglQuerySurface");
256    eglQuerySurface(dpy, surface, EGL_HEIGHT, &h);
257    checkEglError("eglQuerySurface");
258    GLint dim = w < h ? w : h;
259
260    fprintf(stderr, "Window dimensions: %d x %d\n", w, h);
261
262    printGLString("Version", GL_VERSION);
263    printGLString("Vendor", GL_VENDOR);
264    printGLString("Renderer", GL_RENDERER);
265    printGLString("Extensions", GL_EXTENSIONS);
266
267    if(!setupGraphics(w, h)) {
268        fprintf(stderr, "Could not set up graphics.\n");
269        return 0;
270    }
271
272    for (;;) {
273        renderFrame();
274        eglSwapBuffers(dpy, surface);
275        checkEglError("eglSwapBuffers");
276    }
277
278    return 0;
279}
280