New sound and spark for swarmer (#150)

Fix transparent sprites blitting black, due to
still having rgb values despite 0 alpha

particles.json

@@ -5,6 +5,13 @@
       "Name": "spark",
       "OldPic": 111
     },
+    {
+      "Name": "boom",
+      "Sprites": "boom",
+      "OldPic": 111,
+      "Range": 7,
+      "TicksPerFrame": 1
+    },
     {
       "Name": "muzzle_flash_default",
       "Sprites": "muzzle_flash",

sounds/boom.txt

@@ -1,4 +1,4 @@
-Derived from Boom Pack 1 by dklon
-http://opengameart.org/content/boom-pack-1
+Derived from Synthesized_Explosion_01.wav by RSilveira_88
+http://freesound.org/people/RSilveira_88/sounds/216278/
 
 http://creativecommons.org/licenses/by/3.0/

src/cdogs/bullet_class.c

@@ -685,6 +685,8 @@ void BulletInitialize(CArray *bullets)
 	b.RangeLow = b.RangeHigh = 60;
 	b.Power = 20;
 	b.Size = Vec2iNew(3, 3);
+	b.Spark = ParticleClassGet(&gParticleClasses, "boom");
+	b.WallHitSound = StrSound("boom");
 	b.SeekFactor = 20;
 	CArrayPushBack(bullets, &b);
 
@@ -745,10 +747,11 @@ void BulletInitialize(CArray *bullets)
 	b.Beam.Sprites = PicManagerGetSprites(&gPicManager, "swarmer");
 	b.SpeedLow = b.SpeedHigh = 700;
 	b.RangeLow = b.RangeHigh = 70;
-	b.Power = 10;
+	b.Power = 12;
 	b.Size = Vec2iNew(3, 3);
+	b.Spark = ParticleClassGet(&gParticleClasses, "boom");
 	b.WallHitSound = StrSound("boom");
-	b.SeekFactor = 18;
+	b.SeekFactor = 30;
 	CArrayPushBack(bullets, &b);
 
 

src/cdogs/pic_manager.c

@@ -160,13 +160,22 @@ static void AddPic(PicManager *pm, const char *name, const char *path)
 			int srcI = offset.y*image->w + offset.x;
 			for (int i = 0; i < size.x * size.y; i++, srcI++)
 			{
-				Uint32 pixel = ((Uint32 *)s->pixels)[srcI];
-				Uint32 alpha =
+				const Uint32 alpha =
 					((Uint32 *)image->pixels)[srcI] >> image->format->Ashift;
-				Uint32 rgbMask =
-					s->format->Rmask | s->format->Gmask | s->format->Bmask;
-				pic->Data[i] =
-					(pixel & rgbMask) | (alpha << gGraphicsDevice.Ashift);
+				// If completely transparent, replace rgb with black (0) too
+				// This is because transparency blitting checks entire pixel
+				if (alpha == 0)
+				{
+					pic->Data[i] = 0;
+				}
+				else
+				{
+					const Uint32 pixel = ((Uint32 *)s->pixels)[srcI];
+					const Uint32 rgbMask =
+						s->format->Rmask | s->format->Gmask | s->format->Bmask;
+					pic->Data[i] =
+						(pixel & rgbMask) | (alpha << gGraphicsDevice.Ashift);
+				}
 				if ((i + 1) % size.x == 0)
 				{
 					srcI += image->w - size.x;