| // OpenGL ES 1.0 code |
| |
| #include <jni.h> |
| #define LOG_TAG "GLJNI gl_code.cpp" |
| #include <utils/Log.h> |
| |
| #include <GLES/gl.h> |
| |
| #include <stdio.h> |
| |
| #include <stdlib.h> |
| #include <math.h> |
| |
| GLuint texture; |
| GLfloat background; |
| |
| #define FIXED_ONE 0x10000 |
| |
| static void printGLString(const char *name, GLenum s) { |
| const char *v = (const char *) glGetString(s); |
| ALOGI("GL %s = %s\n", name, v); |
| } |
| |
| static void gluLookAt(float eyeX, float eyeY, float eyeZ, |
| float centerX, float centerY, float centerZ, float upX, float upY, |
| float upZ) |
| { |
| // See the OpenGL GLUT documentation for gluLookAt for a description |
| // of the algorithm. We implement it in a straightforward way: |
| |
| float fx = centerX - eyeX; |
| float fy = centerY - eyeY; |
| float fz = centerZ - eyeZ; |
| |
| // Normalize f |
| float rlf = 1.0f / sqrtf(fx*fx + fy*fy + fz*fz); |
| fx *= rlf; |
| fy *= rlf; |
| fz *= rlf; |
| |
| // Normalize up |
| float rlup = 1.0f / sqrtf(upX*upX + upY*upY + upZ*upZ); |
| upX *= rlup; |
| upY *= rlup; |
| upZ *= rlup; |
| |
| // compute s = f x up (x means "cross product") |
| |
| float sx = fy * upZ - fz * upY; |
| float sy = fz * upX - fx * upZ; |
| float sz = fx * upY - fy * upX; |
| |
| // compute u = s x f |
| float ux = sy * fz - sz * fy; |
| float uy = sz * fx - sx * fz; |
| float uz = sx * fy - sy * fx; |
| |
| float m[16] ; |
| m[0] = sx; |
| m[1] = ux; |
| m[2] = -fx; |
| m[3] = 0.0f; |
| |
| m[4] = sy; |
| m[5] = uy; |
| m[6] = -fy; |
| m[7] = 0.0f; |
| |
| m[8] = sz; |
| m[9] = uz; |
| m[10] = -fz; |
| m[11] = 0.0f; |
| |
| m[12] = 0.0f; |
| m[13] = 0.0f; |
| m[14] = 0.0f; |
| m[15] = 1.0f; |
| |
| glMultMatrixf(m); |
| glTranslatef(-eyeX, -eyeY, -eyeZ); |
| } |
| |
| void init_scene(int width, int height) |
| { |
| printGLString("Version", GL_VERSION); |
| printGLString("Vendor", GL_VENDOR); |
| printGLString("Renderer", GL_RENDERER); |
| printGLString("Extensions", GL_EXTENSIONS); |
| |
| glDisable(GL_DITHER); |
| glEnable(GL_CULL_FACE); |
| |
| float ratio = width / height; |
| glViewport(0, 0, width, height); |
| |
| glMatrixMode(GL_PROJECTION); |
| glLoadIdentity(); |
| glFrustumf(-ratio, ratio, -1, 1, 1, 10); |
| |
| glMatrixMode(GL_MODELVIEW); |
| |
| glLoadIdentity(); |
| gluLookAt( |
| 0, 0, 3, // eye |
| 0, 0, 0, // center |
| 0, 1, 0); // up |
| |
| glEnable(GL_TEXTURE_2D); |
| glEnableClientState(GL_VERTEX_ARRAY); |
| glEnableClientState(GL_TEXTURE_COORD_ARRAY); |
| } |
| |
| void create_texture() |
| { |
| const unsigned int on = 0xff0000ff; |
| const unsigned int off = 0xffffffff; |
| const unsigned int pixels[] = |
| { |
| on, off, on, off, on, off, on, off, |
| off, on, off, on, off, on, off, on, |
| on, off, on, off, on, off, on, off, |
| off, on, off, on, off, on, off, on, |
| on, off, on, off, on, off, on, off, |
| off, on, off, on, off, on, off, on, |
| on, off, on, off, on, off, on, off, |
| off, on, off, on, off, on, off, on, |
| }; |
| |
| glGenTextures(1, &texture); |
| glBindTexture(GL_TEXTURE_2D, texture); |
| glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 8, 8, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels); |
| glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); |
| glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); |
| glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); |
| } |
| |
| extern "C" { |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_init(JNIEnv * env, jobject obj, jint width, jint height); |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_step(JNIEnv * env, jobject obj); |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_changeBackground(JNIEnv * env, jobject obj); |
| }; |
| |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_init(JNIEnv * env, jobject obj, jint width, jint height) |
| { |
| init_scene(width, height); |
| create_texture(); |
| } |
| |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_step(JNIEnv * env, jobject obj) |
| { |
| const GLfloat vertices[] = { |
| -1, -1, 0, |
| 1, -1, 0, |
| 1, 1, 0, |
| -1, 1, 0 |
| }; |
| |
| const GLfixed texCoords[] = { |
| 0, 0, |
| FIXED_ONE, 0, |
| FIXED_ONE, FIXED_ONE, |
| 0, FIXED_ONE |
| }; |
| |
| const GLushort quadIndices[] = { 0, 1, 2, 0, 2, 3 }; |
| glVertexPointer(3, GL_FLOAT, 0, vertices); |
| glTexCoordPointer(2, GL_FIXED, 0, texCoords); |
| |
| int nelem = sizeof(quadIndices)/sizeof(quadIndices[0]); |
| static float grey; |
| grey += 0.01f; |
| if (grey > 1.0f) { |
| grey = 0.0f; |
| } |
| glClearColor(background, grey, grey, 1.0f); |
| glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT); |
| glDrawElements(GL_TRIANGLES, nelem, GL_UNSIGNED_SHORT, quadIndices); |
| } |
| |
| JNIEXPORT void JNICALL Java_com_android_gljni_GLJNILib_changeBackground(JNIEnv * env, jobject obj) |
| { |
| background = 1.0f - background; |
| } |