Experimental sun glare effect when directly looking at the sun. Disabled for now, define SUN_DIRECT_VISION_GLARE in OOSunEntity.h to 1 to activate it. Actual direct viewing angle threshold can be maybe adjusted further.

src/Core/Entities/OOSunEntity.h

@@ -35,6 +35,11 @@ MA 02110-1301, USA.
 #define SUN_CORONA_SAMPLES		729			// Samples at half-degree intervals, with a bit of overlap.
 #define MAX_CORONAFLARE			600000.0	// nova flare
 
+#ifndef SUN_DIRECT_VISION_GLARE
+#define	SUN_DIRECT_VISION_GLARE	0
+#define	SUN_DIRECT_VISION_THRESHOLD_ANGLE_COS	0.9945f	// 6 degrees
+#endif
+
 
 @class ShipEntity;
 
@@ -80,6 +85,6 @@ MA 02110-1301, USA.
 - (void) setGoingNova:(BOOL) yesno inTime:(double)interval;
 
 - (void) drawStarGlare;
-
+- (void) drawDirectVisionSunGlare;
 
 @end

src/Core/Entities/OOSunEntity.m

@@ -555,6 +555,39 @@ MA 02110-1301, USA.
 }
 
 
+
+#if SUN_DIRECT_VISION_GLARE
+- (void) drawDirectVisionSunGlare
+{
+	OO_ENTER_OPENGL();
+	
+	OOSetOpenGLState(OPENGL_STATE_OVERLAY);
+	
+	GLfloat	directVisionSunGlare = [PLAYER lookingAtSunWithThresholdAngleCos:SUN_DIRECT_VISION_THRESHOLD_ANGLE_COS];
+	if (directVisionSunGlare)
+	{
+		NSSize	siz =	[[UNIVERSE gui]	size];
+		GLfloat z = [[UNIVERSE gameView] display_z];
+		GLfloat directVisionSunGlareColor[4] = {discColor[0], discColor[1], discColor[2], directVisionSunGlare};
+		
+		OOGL(glColor4fv(directVisionSunGlareColor));
+		
+		OOGLBEGIN(GL_QUADS);
+		glVertex3f(siz.width, siz.height, z);
+		glVertex3f(siz.width, -siz.height, z);
+		glVertex3f(-siz.width, -siz.height, z);
+		glVertex3f(-siz.width, siz.height, z);
+		OOGLEND();
+	}
+}
+#else
+- (void) drawDirectVisionSunGlare
+{
+	// do nothing
+}
+#endif
+
+
 - (void) drawStarGlare
 {
 	OO_ENTER_OPENGL();

src/Core/Entities/PlayerEntity.h

@@ -1004,6 +1004,14 @@ typedef enum
 
 - (void) doGuiScreenResizeUpdates;
 
+/* This method returns a value between 0.0f and 1.0f, depending on how directly our view point
+   faces the sun and is used for generating the "staring at the sun" glare effect. 0.0f means that
+   we are not facing the sun, 1.0f means that we are looking directly at it. The cosine of the 
+   threshold angle between player view point and sun, below which we consider the player as looking
+   at the sun, is passed as parameter to the method.
+*/
+- (GLfloat) lookingAtSunWithThresholdAngleCos:(GLfloat) thresholdAngleCos;
+
 @end
 
 

src/Core/Entities/PlayerEntity.m

@@ -1966,6 +1966,43 @@ static GLfloat		sBaseMass = 0.0;
 }
 
 
+- (GLfloat) lookingAtSunWithThresholdAngleCos:(GLfloat) thresholdAngleCos
+{
+	OOSunEntity	*sun = [UNIVERSE sun];
+	GLfloat measuredCos = 999.0f, measuredCosAbs, sunBrightness = 0.0f;
+	Vector relativePosition, unitRelativePosition;
+	
+	if (!sun)  return 0.0f;
+	
+	relativePosition = HPVectorToVector(HPvector_subtract([self viewpointPosition], [sun position]));
+	unitRelativePosition = vector_normal_or_zbasis(relativePosition);
+	switch ([UNIVERSE viewDirection])
+	{
+		case VIEW_FORWARD:
+			measuredCos = -dot_product(unitRelativePosition, v_forward);
+			break;
+		case VIEW_AFT:
+			measuredCos = +dot_product(unitRelativePosition, v_forward);
+			break;
+		case VIEW_PORT:
+			measuredCos = +dot_product(unitRelativePosition, v_right);
+			break;
+		case VIEW_STARBOARD:
+			measuredCos = -dot_product(unitRelativePosition, v_right);
+			break;
+		default:
+			break;
+	}
+	measuredCosAbs = fabs(measuredCos);
+	if (thresholdAngleCos < measuredCosAbs && measuredCosAbs < 1.0f)	// angle from viewpoint to sun < 10 deg
+	{
+		sunBrightness =  (measuredCos - thresholdAngleCos) / (1.0f - thresholdAngleCos);
+		if (sunBrightness < 0.0f)  sunBrightness = 0.0f;
+	}
+	return sunBrightness;
+}
+
+
 #ifndef NDEBUG
 #define STAGE_TRACKING_BEGIN	{ \
 									NSString * volatile updateStage = @"initialisation"; \

src/Core/Universe.m

@@ -4323,6 +4323,7 @@ static const OOMatrix	starboard_matrix =
 			{
 				if (cachedSun)
 				{
+					[cachedSun drawDirectVisionSunGlare];
 					[cachedSun drawStarGlare];
 				}
 			}