many fixes to image loader, voxel cone tracing, etc.

drivers/gles3/shaders/ssao_blur.glsl

@@ -24,7 +24,7 @@ layout(location = 0) out float visibility;
 // Tunable Parameters:
 
 /** Increase to make depth edges crisper. Decrease to reduce flicker. */
-#define EDGE_SHARPNESS     (1.0)
+#define EDGE_SHARPNESS     (4.0)
 
 /** Step in 2-pixel intervals since we already blurred against neighbors in the
     first AO pass.  This constant can be increased while R decreases to improve

drivers/png/image_loader_png.cpp

@@ -256,6 +256,7 @@ static Ref<Image> _load_mem_png(const uint8_t *p_png, int p_size) {
 static Ref<Image> _lossless_unpack_png(const PoolVector<uint8_t> &p_data) {
 
 	int len = p_data.size();
+	ERR_FAIL_COND_V(len < 4, Ref<Image>());
 	PoolVector<uint8_t>::Read r = p_data.read();
 	ERR_FAIL_COND_V(r[0] != 'P' || r[1] != 'N' || r[2] != 'G' || r[3] != ' ', Ref<Image>());
 	return _load_mem_png(&r[4], len - 4);

modules/squish/image_compress_squish.cpp

@@ -153,8 +153,8 @@ void image_compress_squish(Image *p_image, bool p_srgb) {
 			int bh = h % 4 != 0 ? h + (4 - h % 4) : h;
 
 			int src_ofs = p_image->get_mipmap_offset(i);
-			squish::CompressImage(&rb[src_ofs], bw, bh, &wb[dst_ofs], squish_comp);
-			dst_ofs += (MAX(4, w) * MAX(4, h)) >> shift;
+			squish::CompressImage(&rb[src_ofs], w, h, &wb[dst_ofs], squish_comp);
+			dst_ofs += (MAX(4, bw) * MAX(4, bh)) >> shift;
 			w >>= 1;
 			h >>= 1;
 		}

scene/3d/gi_probe.cpp

@@ -909,10 +909,11 @@ Vector<Color> GIProbe::_get_bake_texture(Ref<Image> p_image, const Color &p_colo
 
 	for (int i = 0; i < bake_texture_size * bake_texture_size; i++) {
 		Color c;
-		c.r = r[i * 4 + 0] / 255.0;
-		c.g = r[i * 4 + 1] / 255.0;
-		c.b = r[i * 4 + 2] / 255.0;
+		c.r = (r[i * 4 + 0] / 255.0) * p_color.r;
+		c.g = (r[i * 4 + 1] / 255.0) * p_color.g;
+		c.b = (r[i * 4 + 2] / 255.0) * p_color.b;
 		c.a = r[i * 4 + 3] / 255.0;
+
 		ret[i] = c;
 	}
 

scene/resources/texture.cpp

@@ -494,9 +494,9 @@ Error StreamTexture::_load_data(const String &p_path, int &tw, int &th, int &fla
 				img = Image::lossy_unpacker(pv);
 			}
 
-			if (img.is_null()) {
+			if (img.is_null() || img->empty()) {
 				memdelete(f);
-				ERR_FAIL_COND_V(img->empty(), ERR_FILE_CORRUPT);
+				ERR_FAIL_COND_V(img.is_null() || img->empty(), ERR_FILE_CORRUPT);
 			}
 
 			total_size += img->get_data().size();