/**
* Initializes a framebuffer object, using the given width and height as
* a guide. See OGLSD_InitTextureObject() and OGLSD_InitFBObject()
* for more information.
*/
JNIEXPORT jboolean JNICALL
Java_sun_java2d_opengl_OGLSurfaceData_initFBObject
(JNIEnv *env, jobject oglsd,
jlong pData, jboolean isOpaque,
jboolean texNonPow2, jboolean texRect,
jint width, jint height)
{
OGLSDOps *oglsdo = (OGLSDOps *)jlong_to_ptr(pData);
GLuint fbobjectID, depthID;
J2dTraceLn2(J2D_TRACE_INFO,
"OGLSurfaceData_initFBObject: w=%d h=%d",
width, height);
if (oglsdo == NULL) {
J2dRlsTraceLn(J2D_TRACE_ERROR,
"OGLSurfaceData_initFBObject: ops are null");
return JNI_FALSE;
}
// initialize color texture object
if (!OGLSD_InitTextureObject(oglsdo, isOpaque, texNonPow2, texRect,
width, height))
{
J2dRlsTraceLn(J2D_TRACE_ERROR,
"OGLSurfaceData_initFBObject: could not init texture object");
return JNI_FALSE;
}
// initialize framebuffer object using color texture created above
if (!OGLSD_InitFBObject(&fbobjectID, &depthID,
oglsdo->textureID, oglsdo->textureTarget,
oglsdo->textureWidth, oglsdo->textureHeight))
{
J2dRlsTraceLn(J2D_TRACE_ERROR,
"OGLSurfaceData_initFBObject: could not init fbobject");
j2d_glDeleteTextures(1, &oglsdo->textureID);
return JNI_FALSE;
}
oglsdo->drawableType = OGLSD_FBOBJECT;
// other fields (e.g. width, height) are set in OGLSD_InitTextureObject()
oglsdo->fbobjectID = fbobjectID;
oglsdo->depthID = depthID;
OGLSD_SetNativeDimensions(env, oglsdo,
oglsdo->textureWidth, oglsdo->textureHeight);
// framebuffer objects differ from other OpenGL surfaces in that the
// value passed to glRead/DrawBuffer() must be GL_COLOR_ATTACHMENTn_EXT,
// rather than GL_FRONT (or GL_BACK)
oglsdo->activeBuffer = GL_COLOR_ATTACHMENT0_EXT;
return JNI_TRUE;
}
/**
* Returns JNI_TRUE only if all of the following conditions are met:
* - the GL_EXT_framebuffer_object extension is available
* - FBO support has been enabled via the system property
* - we can successfully create an FBO with depth capabilities
*/
static jboolean
OGLContext_IsFBObjectExtensionAvailable(JNIEnv *env,
const char *extString)
{
jboolean isFBObjectEnabled = JNI_FALSE;
GLuint fbobjectID, textureID, depthID;
jint width = 1, height = 1;
J2dTraceLn(J2D_TRACE_INFO, "OGLContext_IsFBObjectExtensionAvailable");
// first see if the fbobject extension is available
if (!OGLContext_IsExtensionAvailable(extString,
"GL_EXT_framebuffer_object"))
{
return JNI_FALSE;
}
// next see if the depth texture extension is available
if (!OGLContext_IsExtensionAvailable(extString,
"GL_ARB_depth_texture"))
{
return JNI_FALSE;
}
// next see if the fbobject system property has been enabled
isFBObjectEnabled =
JNU_GetStaticFieldByName(env, NULL,
"sun/java2d/opengl/OGLSurfaceData",
"isFBObjectEnabled", "Z").z;
if (!isFBObjectEnabled) {
J2dRlsTraceLn(J2D_TRACE_INFO,
"OGLContext_IsFBObjectExtensionAvailable: disabled via flag");
return JNI_FALSE;
}
// finally, create a dummy fbobject with depth capabilities to see
// if this configuration is supported by the drivers/hardware
// (first we initialize a color texture object that will be used to
// construct the dummy fbobject)
j2d_glGenTextures(1, &textureID);
j2d_glBindTexture(GL_TEXTURE_2D, textureID);
j2d_glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
width, height, 0,
GL_RGB, GL_UNSIGNED_BYTE, NULL);
j2d_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
j2d_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
// initialize framebuffer object using color texture created above
if (!OGLSD_InitFBObject(&fbobjectID, &depthID,
textureID, GL_TEXTURE_2D,
width, height))
{
J2dRlsTraceLn(J2D_TRACE_INFO,
"OGLContext_IsFBObjectExtensionAvailable: fbobject unsupported");
j2d_glDeleteTextures(1, &textureID);
return JNI_FALSE;
}
// delete the temporary resources
j2d_glDeleteTextures(1, &textureID);
j2d_glDeleteRenderbuffersEXT(1, &depthID);
j2d_glDeleteFramebuffersEXT(1, &fbobjectID);
J2dRlsTraceLn(J2D_TRACE_INFO,
"OGLContext_IsFBObjectExtensionAvailable: fbobject supported");
return JNI_TRUE;
}