| Address | stdgba | Access | Type | tonclib |
|---|
0x4000050 | reg_bldcnt | RW | blend_control | REG_BLDCNT |
0x4000052 | reg_bldalpha[2] | RW | fixed<unsigned char>[2] | REG_BLDALPHA |
0x4000054 | reg_bldy | RW | fixed<unsigned char> | REG_BLDY |
struct blend_control {
bool dest_bg0 : 1; // 2nd target layers
bool dest_bg1 : 1;
bool dest_bg2 : 1;
bool dest_bg3 : 1;
bool dest_obj : 1;
bool dest_backdrop : 1;
blend_op blend_op : 2; // none / alpha / brighten / darken
bool src_bg0 : 1; // 1st target layers
bool src_bg1 : 1;
bool src_bg2 : 1;
bool src_bg3 : 1;
bool src_obj : 1;
bool src_backdrop : 1;
};
gba::reg_bldcnt = {
.src_bg0 = true,
.dest_bg1 = true,
.blend_op = gba::blend_op_alpha
};
gba::reg_bldalpha[0] = 0.5_fx; // EVA (source weight)
gba::reg_bldalpha[1] = 0.5_fx; // EVB (target weight)