use stb_image for image support

src/gui/image.cpp

@@ -0,0 +1,66 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2023 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * this license only applies to the code. for the license of each font used,
+ * see `papers/`.
+ */
+
+#include "gui.h"
+#include "image.h"
+#include "../ta-log.h"
+
+#define STB_IMAGE_IMPLEMENTATION
+#define STBI_ONLY_PNG
+#define STBI_NO_STDIO
+#include "stb_image.h"
+
+const unsigned char* imageData[GUI_IMAGE_MAX]={
+  image_icon_data
+};
+
+const unsigned int imageLen[GUI_IMAGE_MAX]={
+  image_icon_size
+};
+
+const FurnaceGUIImage* FurnaceGUI::getImage(FurnaceGUIImages image) {
+  FurnaceGUIImage* ret=NULL;
+  auto retPos=images.find(image);
+  if (retPos!=images.cend()) {
+    ret=retPos->second;
+  } else {
+    ret=new FurnaceGUIImage;
+    logV("loading image %d to pool.",(int)image);
+    ret->data=stbi_load_from_memory(imageData[image],imageLen[image],&ret->width,&ret->height,&ret->ch,STBI_rgb_alpha);
+
+    if (ret->data==NULL) {
+      logE("could not load image %d!",(int)image);
+      delete ret;
+      return NULL;
+    }
+
+    logV("%dx%d",ret->width,ret->height);
+
+    images[image]=ret;
+  }
+
+  // warning silencers
+  stbi__addints_valid(2,2);
+  stbi__mul2shorts_valid(2,2);
+
+  return ret;
+}