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authortruelight <truelight@openttd.org>2007-09-09 21:56:52 +0000
committertruelight <truelight@openttd.org>2007-09-09 21:56:52 +0000
commit89bdfaacd93f543a72c37adbb277531f5e39482c (patch)
tree3628ae991fa6f1b731d7c53d8e543a7a18dada9e /src
parent38ff181ebf2e6baa1dfa41828b407bea488c2fa0 (diff)
downloadopenttd-89bdfaacd93f543a72c37adbb277531f5e39482c.tar.xz
(svn r11076) -Fix: MakeTransparent of 32bpp blitter used 0..100; using 0..255 makes it much faster (frosch)
-Fix: ComposeColourXXX could work a tiny bit faster when using 256, not 255 as value to divide with; downside is that it can give alpha errors (frosch)
Diffstat (limited to 'src')
-rw-r--r--src/blitter/32bpp_anim.cpp4
-rw-r--r--src/blitter/32bpp_base.hpp30
-rw-r--r--src/blitter/32bpp_simple.cpp4
3 files changed, 23 insertions, 15 deletions
diff --git a/src/blitter/32bpp_anim.cpp b/src/blitter/32bpp_anim.cpp
index 9dbc19fba..7f8fe7651 100644
--- a/src/blitter/32bpp_anim.cpp
+++ b/src/blitter/32bpp_anim.cpp
@@ -59,7 +59,7 @@ void Blitter_32bppAnim::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomL
/* Make the current color a bit more black, so it looks like this image is transparent */
if (src->a != 0) {
- *dst = MakeTransparent(*dst, 75);
+ *dst = MakeTransparent(*dst, 192);
*anim = bp->remap[*anim];
}
break;
@@ -90,7 +90,7 @@ void Blitter_32bppAnim::DrawColorMappingRect(void *dst, int width, int height, i
if (pal == PALETTE_TO_TRANSPARENT) {
do {
for (int i = 0; i != width; i++) {
- *udst = MakeTransparent(*udst, 60);
+ *udst = MakeTransparent(*udst, 154);
*anim = 0;
udst++;
anim++;
diff --git a/src/blitter/32bpp_base.hpp b/src/blitter/32bpp_base.hpp
index 3fce0951a..51afea336 100644
--- a/src/blitter/32bpp_base.hpp
+++ b/src/blitter/32bpp_base.hpp
@@ -48,15 +48,19 @@ public:
*/
static inline uint ComposeColourRGBA(uint r, uint g, uint b, uint a, uint current)
{
+ if (a == 0) return current;
+ if (a >= 255) return ComposeColour(0xFF, r, g, b);
+
uint cr, cg, cb;
cr = GB(current, 16, 8);
cg = GB(current, 8, 8);
cb = GB(current, 0, 8);
+ /* The 256 is wrong, it should be 255, but 256 is much faster... */
return ComposeColour(0xFF,
- (r * a + cr * (255 - a)) / 255,
- (g * a + cg * (255 - a)) / 255,
- (b * a + cb * (255 - a)) / 255);
+ (r * a + cr * (256 - a)) / 256,
+ (g * a + cg * (256 - a)) / 256,
+ (b * a + cb * (256 - a)) / 256);
}
/**
@@ -64,24 +68,28 @@ public:
*/
static inline uint ComposeColourPA(uint colour, uint a, uint current)
{
+ if (a == 0) return current;
+ if (a >= 255) return (colour | 0xFF000000);
+
uint r, g, b, cr, cg, cb;
- r = GB(colour, 16, 8);
- g = GB(colour, 8, 8);
- b = GB(colour, 0, 8);
+ r = GB(colour, 16, 8);
+ g = GB(colour, 8, 8);
+ b = GB(colour, 0, 8);
cr = GB(current, 16, 8);
cg = GB(current, 8, 8);
cb = GB(current, 0, 8);
+ /* The 256 is wrong, it should be 255, but 256 is much faster... */
return ComposeColour(0xFF,
- (r * a + cr * (255 - a)) / 255,
- (g * a + cg * (255 - a)) / 255,
- (b * a + cb * (255 - a)) / 255);
+ (r * a + cr * (256 - a)) / 256,
+ (g * a + cg * (256 - a)) / 256,
+ (b * a + cb * (256 - a)) / 256);
}
/**
* Make a pixel looks like it is transparent.
* @param colour the colour already on the screen.
- * @param amount the amount of transparency, times 100.
+ * @param amount the amount of transparency, times 256.
* @return the new colour for the screen.
*/
static inline uint MakeTransparent(uint colour, uint amount)
@@ -91,7 +99,7 @@ public:
g = GB(colour, 8, 8);
b = GB(colour, 0, 8);
- return ComposeColour(0xFF, r * amount / 100, g * amount / 100, b * amount / 100);
+ return ComposeColour(0xFF, r * amount / 256, g * amount / 256, b * amount / 256);
}
/**
diff --git a/src/blitter/32bpp_simple.cpp b/src/blitter/32bpp_simple.cpp
index 6dbdd2267..b5afea9eb 100644
--- a/src/blitter/32bpp_simple.cpp
+++ b/src/blitter/32bpp_simple.cpp
@@ -40,7 +40,7 @@ void Blitter_32bppSimple::Draw(Blitter::BlitterParams *bp, BlitterMode mode, Zoo
* we produce a result the newgrf maker didn't expect ;) */
/* Make the current color a bit more black, so it looks like this image is transparent */
- if (src->a != 0) *dst = MakeTransparent(*dst, 75);
+ if (src->a != 0) *dst = MakeTransparent(*dst, 192);
break;
default:
@@ -60,7 +60,7 @@ void Blitter_32bppSimple::DrawColorMappingRect(void *dst, int width, int height,
if (pal == PALETTE_TO_TRANSPARENT) {
do {
for (int i = 0; i != width; i++) {
- *udst = MakeTransparent(*udst, 60);
+ *udst = MakeTransparent(*udst, 154);
udst++;
}
udst = udst - width + _screen.pitch;