add setProgress

And an example program to demo it.

Uses signalConnect, see #191

Author: jcupitt

examples/progress.php

@@ -0,0 +1,28 @@
+#!/usr/bin/env php 
+<?php
+
+require __DIR__ . '/../vendor/autoload.php';
+use Jcupitt\Vips;
+
+# Vips\Config::setLogger(new Vips\DebugLogger());
+
+$image = Vips\Image::black(1, 1000000);
+$image->setProgress(true);
+    
+$image->signalConnect("preeval", function($image, $progress) {
+    echo "preeval:\n";
+});
+$image->signalConnect("eval", function($image, $progress) {
+    echo "eval: $progress->percent % complete\r";
+}); 
+    
+$image->signalConnect("posteval", function($image, $progress) {
+    echo "\nposteval:\n";
+});
+    
+// trigger evaluation
+$image->avg();
+    
+$image = null;
+
+Vips\FFI::shutDown();

src/FFI.php

@@ -808,6 +808,7 @@ private static function init(): void
             "VipsSourceCustom" => self::$vips->type("VipsSourceCustom*"),
             "VipsTarget" => self::$vips->type("VipsTarget*"),
             "VipsTargetCustom" => self::$vips->type("VipsTargetCustom*"),
+            "VipsProgress" => self::$vips->type("VipsProgress*"),
         ];
 
         self::$gtypes = [

src/GObject.php

@@ -128,7 +128,7 @@ private static function getMarshaler(string $name, callable $callback): ?Closure
                     CData  $hint,
                     ?CData $data
                 ) use (&$callback) {
-                    assert($numberOfParams === 3);
+                    assert($numberOfParams === 2);
                     /**
                      * Signature: void(VipsImage* image, void* progress, void* handle)
                      */

src/Image.php

@@ -1296,6 +1296,23 @@ public function remove(string $name): void
         }
     }
 
+    /**
+     * Enable progress reporting on an image.
+     *
+     * The preeval, eval and posteval signals will be emitted on the 
+     * most-downstream image for which setProgress() was enabled. @see
+     * GObject::signalConnect().
+     *
+     * @param bool $progress TRUE to enable progress reporting.
+     *
+     * @return void
+     */
+    public function setProgress(bool $progress): void
+    {
+        FFI::vips()->vips_image_set_progress($this->pointer, $progress);
+
+    }
+
     /**
      * Makes a string-ified version of the Image.
      *