From 41b2f9b9112cc4872b51a13928afd99718f3d68f Mon Sep 17 00:00:00 2001
From: Nail <nailsonnego@gmail.com>
Date: Fri, 4 Apr 2014 12:58:12 -0300
Subject: [PATCH] Per-pixel transparency.

---
 modules/gamelib/const.lua        | 1 +
 src/client/const.h               | 1 +
 src/client/spritemanager.cpp     | 8 ++++++--
 src/framework/graphics/image.cpp | 2 +-
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/modules/gamelib/const.lua b/modules/gamelib/const.lua
index 06b4f5d7..3d2e53f6 100644
--- a/modules/gamelib/const.lua
+++ b/modules/gamelib/const.lua
@@ -105,6 +105,7 @@ GameNewOutfitProtocol = 49
 GamePVPMode = 50
 GameWritableDate = 51
 GameAdditionalVipInfo = 52
+GameSpritesAlphaChannel = 56
 
 TextColors = {
   red       = '#f55e5e', --'#c83200'
diff --git a/src/client/const.h b/src/client/const.h
index f11f0fc1..0b4e85c6 100644
--- a/src/client/const.h
+++ b/src/client/const.h
@@ -387,6 +387,7 @@ namespace Otc
         GameBaseSkillU16 = 53,
         GameCreatureIcons = 54,
         GameHideNpcNames = 55,
+        GameSpritesAlphaChannel = 56,
 
         LastGameFeature = 101
     };
diff --git a/src/client/spritemanager.cpp b/src/client/spritemanager.cpp
index a99fea88..7cda6dca 100644
--- a/src/client/spritemanager.cpp
+++ b/src/client/spritemanager.cpp
@@ -81,6 +81,7 @@ void SpriteManager::saveSpr(std::string fileName)
         else
             fin->addU16(m_spritesCount);
 
+        bool useAlpha = g_game.getFeature(Otc::GameSpritesAlphaChannel);
         uint32 offset = fin->tell();
         uint32 spriteAddress = offset + 4 * m_spritesCount;
         for(int i = 1; i <= m_spritesCount; i++)
@@ -98,6 +99,7 @@ void SpriteManager::saveSpr(std::string fileName)
                 fin->addU8(m_spritesFile->getU8());
                 fin->addU8(m_spritesFile->getU8());
                 fin->addU8(m_spritesFile->getU8());
+                if (useAlpha) fin->addU8(m_spritesFile->getU8());
 
                 uint16 dataSize = m_spritesFile->getU16();
                 fin->addU16(dataSize);
@@ -153,6 +155,8 @@ ImagePtr SpriteManager::getSpriteImage(int id)
         uint8 *pixels = image->getPixelData();
         int writePos = 0;
         int read = 0;
+        bool useAlpha = g_game.getFeature(Otc::GameSpritesAlphaChannel);
+        uint8 channels = useAlpha ? 4 : 3;
 
         // decompress pixels
         while(read < pixelDataSize && writePos < SPRITE_DATA_SIZE) {
@@ -171,11 +175,11 @@ ImagePtr SpriteManager::getSpriteImage(int id)
                 pixels[writePos + 0] = m_spritesFile->getU8();
                 pixels[writePos + 1] = m_spritesFile->getU8();
                 pixels[writePos + 2] = m_spritesFile->getU8();
-                pixels[writePos + 3] = 0xFF;
+                pixels[writePos + 3] = useAlpha ? m_spritesFile->getU8() : 0xFF;
                 writePos += 4;
             }
 
-            read += 4 + (3 * coloredPixels);
+            read += 4 + (channels * coloredPixels);
         }
 
         // fill remaining pixels with alpha
diff --git a/src/framework/graphics/image.cpp b/src/framework/graphics/image.cpp
index c7d79197..8f3bfe00 100644
--- a/src/framework/graphics/image.cpp
+++ b/src/framework/graphics/image.cpp
@@ -110,7 +110,7 @@ void Image::blit(const Point& dest, const ImagePtr& other)
         int y = p / other->getWidth();
         int pos = ((dest.y + y) * m_size.width() + (dest.x + x)) * 4;
 
-        if(otherPixels[p*4+3] == 0xFF) {
+        if (otherPixels[p*4+3] != 0) {
             m_pixels[pos+0] = otherPixels[p*4+0];
             m_pixels[pos+1] = otherPixels[p*4+1];
             m_pixels[pos+2] = otherPixels[p*4+2];