diff options
author | 2021-04-06 17:24:21 +0200 | |
---|---|---|
committer | 2021-04-07 01:24:21 +1000 | |
commit | d919a1e095674c02679247d751e1c229b2b3e305 (patch) | |
tree | af12b83f8bf5a90959babc4e60ff540866dd8de4 | |
parent | d28b2031c4b1cf886f05e2a24b94ef589051057b (diff) |
machine/spg_renderer.cpp: Fixed incorrect handling of 2-bit blend level. (#7932) [Ryan Holtz, simer]
-rw-r--r-- | src/devices/machine/spg_renderer.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/src/devices/machine/spg_renderer.cpp b/src/devices/machine/spg_renderer.cpp index 255e8369125..a4171697095 100644 --- a/src/devices/machine/spg_renderer.cpp +++ b/src/devices/machine/spg_renderer.cpp @@ -653,7 +653,11 @@ void spg_renderer_device::draw_sprite(bool read_from_csspace, int extended_sprit const uint8_t bpp = attr & 0x0003; const uint32_t nc_bpp = ((bpp)+1) << 1; const uint32_t bits_per_row = nc_bpp * tile_w / 16; - uint8_t blendlevel = (m_video_regs_2a & 3) << 3; + + // Max blend level (3) should result in 100% opacity on the sprite, per docs + // Min blend level (0) should result in 25% opacity on the sprite, per docs + static const uint8_t s_blend_levels[4] = { 0x08, 0x10, 0x18, 0x20 }; + uint8_t blendlevel = s_blend_levels[m_video_regs_2a & 3]; uint32_t words_per_tile; |