themes-wordpress/sketch/inc/jetpack.php

<?php
/**
 * Jetpack Compatibility File
 * See: http://jetpack.me/
 *
 * @package Sketch
 */

/**
 * Add theme support for Infinite Scroll.
 * See: http://jetpack.me/support/infinite-scroll/
 */

function sketch_jetpack_setup() {
	add_theme_support( 'infinite-scroll', array(
		'container'      => 'main',
        'posts_per_page' => 9,
		'footer'         => 'page',
		'render'         => 'sketch_infinite_scroll_render',
		'wrapper'        => false,
	) );

	add_theme_support( 'featured-content', array(
	    'filter'     => 'sketch_get_featured_posts',
	    'max_posts'  => 10,
	    'post_types' => array( 'post', 'page', 'jetpack-portfolio' ),
	) );

    /**
     * Add theme support for Responsive Videos.
     */
    add_theme_support( 'jetpack-responsive-videos' );

    /**
     * Add theme support for Jetpack portfolios
     */
    add_theme_support( 'jetpack-portfolio', array(
		'title'          => true,
		'content'        => true,
		'featured-image' => true,
	) );

    /**
     * Add theme support for site logos
     */
     add_theme_support( 'site-logo', array(
     	'size' => 'sketch-site-logo'
     ) );
}
add_action( 'after_setup_theme', 'sketch_jetpack_setup' );


/**
 * Define the code that is used to render the posts added by Infinite Scroll.
 *
 * Includes the whole loop. Used to include the correct template part for the Portfolio CPT.
 */
function sketch_infinite_scroll_render() {
	while ( have_posts() ) {
		the_post();

		if ( is_post_type_archive( 'jetpack-portfolio' ) || is_tax( 'jetpack-portfolio-type' ) || is_tax( 'jetpack-portfolio-tag' ) ) {
			get_template_part( 'content', 'portfolio' );
		} else {
			get_template_part( 'content', get_post_format() );
		}
	}
}

function sketch_get_featured_posts() {
    return apply_filters( 'sketch_get_featured_posts', array() );
}

function sketch_has_featured_posts( $minimum = 1 ) {
    if ( is_paged() )
        return false;

    $minimum = absint( $minimum );
    $featured_posts = apply_filters( 'sketch_get_featured_posts', array() );

    if ( ! is_array( $featured_posts ) )
        return false;

    if ( $minimum > count( $featured_posts ) )
        return false;

    return true;
}

/**
 * Portfolio Title.
 */
function sketch_portfolio_title( $before = '', $after = '' ) {
	$jetpack_portfolio_title = get_option( 'jetpack_portfolio_title' );
	$title = '';

	if ( is_post_type_archive( 'jetpack-portfolio' ) ) {
		if ( isset( $jetpack_portfolio_title ) && '' != $jetpack_portfolio_title ) {
			$title = esc_html( $jetpack_portfolio_title );
		} else {
			$title = post_type_archive_title( '', false );
		}
	} elseif ( is_tax( 'jetpack-portfolio-type' ) || is_tax( 'jetpack-portfolio-tag' ) ) {
		$title = single_term_title( '', false );
	}

	echo $before . $title . $after;
}

/**
 * Portfolio Content.
 */
function sketch_portfolio_content( $before = '', $after = '' ) {
	$jetpack_portfolio_content = get_option( 'jetpack_portfolio_content' );

	if ( is_tax() && get_the_archive_description() ) {
		echo $before . get_the_archive_description() . $after;
	} else if ( isset( $jetpack_portfolio_content ) && '' != $jetpack_portfolio_content ) {
		$content = convert_chars( convert_smilies( wptexturize( wp_kses_post( $jetpack_portfolio_content ) ) ) );
		echo $before . $content . $after;
	}
}

/**
 * Portfolio Featured Image.
 */
function sketch_portfolio_featured_image( $before = '', $after = '' ) {
	$jetpack_portfolio_featured_image = get_option( 'jetpack_portfolio_featured_image' );

	if ( isset( $jetpack_portfolio_featured_image ) && '' != $jetpack_portfolio_featured_image ) {
		$featured_image = wp_get_attachment_image( (int) $jetpack_portfolio_featured_image, 'sketch-featured' );
		echo $before . $featured_image . $after;
	}
}

/**
 * Filter Infinite Scroll text handle.
 */
function sketch_portfolio_infinite_scroll_navigation( $js_settings ) {
	if ( is_post_type_archive( 'jetpack-portfolio' ) || is_tax( 'jetpack-portfolio-type' ) || is_tax( 'jetpack-portfolio-tag' ) ) {
		$js_settings[ 'text' ] = esc_js( esc_html__( 'Older projects', 'sketch' ) );
	}

	return $js_settings;
}
add_filter( 'infinite_scroll_js_settings', 'sketch_portfolio_infinite_scroll_navigation' );