Add animated_image[] formspec element (#9258)

1 files changed, 83 insertions, 0 deletions

diff --git a/src/gui/guiAnimatedImage.cpp b/src/gui/guiAnimatedImage.cpp
new file mode 100644
index 000000000..822304087
--- /dev/null
+++ b/src/gui/guiAnimatedImage.cpp
@@ -0,0 +1,83 @@
+#include "guiAnimatedImage.h"
+
+#include "client/guiscalingfilter.h"
+#include "client/tile.h" // ITextureSource
+#include "log.h"
+#include "porting.h"
+#include <string>
+
+GUIAnimatedImage::GUIAnimatedImage(gui::IGUIEnvironment *env, gui::IGUIElement *parent,
+		s32 id, const core::rect<s32> &rectangle, const std::string &name,
+		ISimpleTextureSource *tsrc) :
+		gui::IGUIElement(gui::EGUIET_ELEMENT, env, parent, id, rectangle),
+		m_name(name), m_tsrc(tsrc), m_texture(nullptr), m_global_time(0),
+		m_frame_idx(0), m_frame_count(1), m_frame_duration(1), m_frame_time(0)
+{
+	// Expected format: "texture_name:frame_count,frame_duration"
+	// If this format is not met, the string will be loaded as a normal texture
+
+	std::string::size_type colon_position = name.find(':', 0);
+	std::string::size_type comma_position = name.find(',', 0);
+
+	if (comma_position != std::string::npos &&
+			colon_position != std::string::npos &&
+			comma_position < name.size()) {
+		m_texture = m_tsrc->getTexture(name.substr(0, colon_position));
+
+		m_frame_count = std::max(stoi(name.substr(
+					colon_position + 1, comma_position - colon_position - 1)), 1);
+
+		m_frame_duration = std::max(stoi(name.substr(comma_position + 1)), 1);
+	} else {
+		// Leave the count/duration and display a static image
+		m_texture = m_tsrc->getTexture(name);
+		errorstream << "animated_image[]: Invalid texture format " << name <<
+			". Expected format: texture_name:frame_count,frame_duration" << std::endl;
+	}
+
+	if (m_texture != nullptr) {
+		core::dimension2d<u32> size = m_texture->getOriginalSize();
+		if (size.Height < (u64)m_frame_count) {
+			m_frame_count = size.Height;
+		}
+	} else {
+		// No need to step an animation if we have nothing to draw
+		m_frame_count = 1;
+	}
+}
+
+void GUIAnimatedImage::draw()
+{
+	// Render the current frame
+	if (m_texture != nullptr) {
+		video::IVideoDriver *driver = Environment->getVideoDriver();
+
+		const video::SColor color(255, 255, 255, 255);
+		const video::SColor colors[] = {color, color, color, color};
+
+		core::dimension2d<u32> size = m_texture->getOriginalSize();
+		size.Height /= m_frame_count;
+
+		draw2DImageFilterScaled( driver, m_texture, AbsoluteRect,
+				core::rect<s32>(core::position2d<s32>(0, size.Height * m_frame_idx), size),
+				NoClip ? nullptr : &AbsoluteClippingRect, colors, true);
+	}
+
+	// Step the animation
+	if (m_frame_count > 1) {
+		// Determine the delta time to step
+		u64 new_global_time = porting::getTimeMs();
+		if (m_global_time > 0)
+			m_frame_time += new_global_time - m_global_time;
+
+		m_global_time = new_global_time;
+
+		// Advance by the number of elapsed frames, looping if necessary
+		m_frame_idx += u32(m_frame_time / m_frame_duration);
+		m_frame_idx %= m_frame_count;
+
+		// If 1 or more frames have elapsed, reset the frame time counter with
+		// the remainder
+		m_frame_time %= m_frame_duration;
+	}
+}