Open source Star Ruler 2 source code!

source/game/scene/icon_node.cpp

@@ -0,0 +1,66 @@
+#include "icon_node.h"
+#include "render/driver.h"
+#include "render/spritesheet.h"
+#include "obj/object.h"
+#include "frustum.h"
+
+const double MinRenderDistanceFactor = 5000.0;
+
+namespace scene {
+	
+
+	IconNode::IconNode(const render::SpriteSheet* spriteSheet, unsigned spriteIndex) : sheet(spriteSheet), index(spriteIndex) {
+		setFlag(NF_NoMatrix, true);
+		if(spriteSheet->material.baseMat != render::MAT_Solid)
+			setFlag(NF_Transparent, true);
+	}
+
+	bool IconNode::preRender(render::RenderDriver& driver) {
+		auto fromCamera = abs_position + (driver.cam_facing * abs_scale) - driver.cam_pos;
+		sortDistance = fromCamera.getLength();
+
+		if(sortDistance < MinRenderDistanceFactor * abs_scale || !driver.getViewFrustum().overlaps(abs_position,abs_scale))
+			return false;
+		else
+			return true;
+	}
+
+	void IconNode::render(render::RenderDriver& driver) {
+		double iconScale = sortDistance * abs_scale * 0.25;
+		bool selected = false;
+		if(obj)
+			selected = obj->getFlag(objSelected);
+		if(selected)
+			iconScale *= 1.1;
+
+		//Calculate best-fit facing of the 2D sprite (Assuming the sprite is facing +x)
+		auto& cam_up = driver.cam_up;
+		auto& cam_facing = driver.cam_facing;
+
+		double rot;
+
+		vec3d obj_facing = rotation * vec3d::front();
+		double alongDot = cam_facing.dot(obj_facing);
+
+		//If it's facing along the camera vector, we can't get an accurate angle
+		if(alongDot > -0.999 && alongDot < 0.999) {
+			obj_facing -= cam_facing * alongDot;
+			obj_facing.normalize();
+
+			vec3d cam_right = cam_up.cross(cam_facing);
+			rot = acos(cam_right.dot(obj_facing));
+			if(cam_up.dot(obj_facing) < 0)
+				rot = -rot;
+		}
+		else {
+			//Point up when going away, down when coming toward
+			rot = alongDot > 0 ? pi * 0.5 : pi * -0.5;
+		}
+
+		driver.drawBillboard(abs_position, iconScale,
+			sheet->material, sheet->getSource(index), rot);
+
+		//TODO: Draw other icons based on group unit count
+	}
+
+};