1 files changed, 53 insertions, 44 deletions

diff --git a/extension/src/openvic-extension/classes/GFXPieChartTexture.cpp b/extension/src/openvic-extension/classes/GFXPieChartTexture.cpp
index 417566d..5d955a3 100644
--- a/extension/src/openvic-extension/classes/GFXPieChartTexture.cpp
+++ b/extension/src/openvic-extension/classes/GFXPieChartTexture.cpp
@@ -7,6 +7,7 @@
 
 using namespace godot;
 using namespace OpenVic;
+using namespace OpenVic::Utilities::literals;
 
 StringName const& GFXPieChartTexture::_slice_identifier_key() {
 	static const StringName slice_identifier_key = "identifier";
@@ -21,7 +22,35 @@ StringName const& GFXPieChartTexture::_slice_weight_key() {
 	return slice_weight_key;
 }
 
-static constexpr float TWO_PI = 2.0f * std::numbers::pi_v<float>;
+GFXPieChartTexture::slice_t const* GFXPieChartTexture::get_slice(Vector2 const& position) const {
+	if (slices.empty() || position.length_squared() > 1.0_real) {
+		return nullptr;
+	}
+
+	static constexpr float TWO_PI = 2.0f * std::numbers::pi_v<float>;
+
+	/* Calculate the anti-clockwise angle between the point and the centre of the image.
+	 * The y coordinate is negated as the image coordinate system's y increases downwards. */
+	float theta = atan2(-position.y, position.x);
+	if (theta < 0.0f) {
+		theta += TWO_PI;
+	}
+
+	/* Rescale angle so that total_weight is a full rotation. */
+	theta *= total_weight / TWO_PI;
+
+	/* Find the slice theta lies in. */
+	for (slice_t const& slice : slices) {
+		theta -= slice.weight;
+
+		if (theta <= 0.0f) {
+			return &slice;
+		}
+	}
+
+	/* Default to the first slice in case theta never reaches 0 due to floating point inaccuracy. */
+	return &slices.front();
+}
 
 Error GFXPieChartTexture::_generate_pie_chart_image() {
 	ERR_FAIL_NULL_V(gfx_pie_chart, FAILED);
@@ -30,60 +59,37 @@ Error GFXPieChartTexture::_generate_pie_chart_image() {
 		vformat("Invalid GFX::PieChart size for GFXPieChartTexture - %d", gfx_pie_chart->get_size())
 	);
 
-	const int32_t pie_chart_size = 2 * gfx_pie_chart->get_size();
+	const int32_t pie_chart_radius = gfx_pie_chart->get_size();
+	const int32_t pie_chart_diameter = 2 * pie_chart_radius;
 
 	/* Whether we've already set the ImageTexture to an image of the right dimensions,
 	 * and so can update it without creating and setting a new image, or not. */
-	const bool can_update = pie_chart_image.is_valid() && pie_chart_image->get_width() == pie_chart_size
-		&& pie_chart_image->get_height() == pie_chart_size;
+	const bool can_update = pie_chart_image.is_valid() && pie_chart_image->get_width() == pie_chart_diameter
+		&& pie_chart_image->get_height() == pie_chart_diameter;
 
 	if (!can_update) {
-		pie_chart_image = Image::create(pie_chart_size, pie_chart_size, false, Image::FORMAT_RGBA8);
+		pie_chart_image = Image::create(pie_chart_diameter, pie_chart_diameter, false, Image::FORMAT_RGBA8);
 		ERR_FAIL_NULL_V(pie_chart_image, FAILED);
 	}
 
 	static const Color background_colour { 0.0f, 0.0f, 0.0f, 0.0f };
 
 	if (!slices.empty()) {
-		const float pie_chart_radius = gfx_pie_chart->get_size();
-
-		const Vector2 centre_translation = Vector2 { 0.5f, 0.5f } - static_cast<Vector2>(pie_chart_image->get_size()) * 0.5f;
-
-		for (Vector2i point { 0, 0 }; point.y < pie_chart_image->get_height(); ++point.y) {
-
-			for (point.x = 0; point.x < pie_chart_image->get_width(); ++point.x) {
-
-				const Vector2 offset = centre_translation + point;
-
-				if (offset.length() <= pie_chart_radius) {
-
-					/* Calculate the anti-clockwise angle between the point and the centre of the image.
-					 * The y coordinate is negated as the image coordinate system's y increases downwards. */
-					float theta = atan2(-offset.y, offset.x);
-					if (theta < 0.0f) {
-						theta += TWO_PI;
-					}
-
-					/* Rescale angle so that total_weight is a full rotation. */
-					theta *= total_weight / TWO_PI;
+		for (Vector2i point { 0, 0 }; point.y < pie_chart_diameter; ++point.y) {
 
-					/* Default to the first colour in case theta never reaches 0 due to floating point inaccuracy. */
-					Color colour = slices.front().first;
+			for (point.x = 0; point.x < pie_chart_diameter; ++point.x) {
 
-					/* Find the slice theta lies in. */
-					for (slice_t const& slice : slices) {
-						theta -= slice.second;
+				Vector2 offset = point;
+				// Move to the centre of the pixel
+				offset += Vector2 { 0.5_real, 0.5_real };
+				// Normalise to [0, 2]
+				offset /= pie_chart_radius;
+				// Translate to [-1, 1]
+				offset -= Vector2 { 1.0_real, 1.0_real };
 
-						if (theta <= 0.0f) {
-							colour = slice.first;
-							break;
-						}
-					}
+				slice_t const* slice = get_slice(offset);
 
-					pie_chart_image->set_pixelv(point, colour);
-				} else {
-					pie_chart_image->set_pixelv(point, background_colour);
-				}
+				pie_chart_image->set_pixelv(point, slice != nullptr ? slice->colour : background_colour);
 			}
 		}
 	} else {
@@ -107,12 +113,15 @@ Error GFXPieChartTexture::set_slices_array(godot_pie_chart_data_t const& new_sli
 	for (int32_t i = 0; i < new_slices.size(); ++i) {
 		Dictionary const& slice_dict = new_slices[i];
 		ERR_CONTINUE_MSG(
-			!slice_dict.has(_slice_colour_key()) || !slice_dict.has(_slice_weight_key()),
+			!slice_dict.has(_slice_identifier_key()) || !slice_dict.has(_slice_colour_key())
+				|| !slice_dict.has(_slice_weight_key()),
 			vformat("Invalid slice keys at index %d", i)
 		);
-		const slice_t slice = std::make_pair(slice_dict[_slice_colour_key()], slice_dict[_slice_weight_key()]);
-		if (slice.second > 0.0f) {
-			total_weight += slice.second;
+		const slice_t slice {
+			slice_dict[_slice_identifier_key()], slice_dict[_slice_colour_key()], slice_dict[_slice_weight_key()]
+		};
+		if (slice.weight > 0.0f) {
+			total_weight += slice.weight;
 			slices.push_back(slice);
 		}
 	}