mirror of
https://github.com/bsnes-emu/bsnes.git
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94b2538af5
byuu says: Basically just a project rename, with s/bsnes/higan and the new icon from lowkee added in. It won't compile on Windows because I forgot to update the resource.rc file, and a path transform command isn't working on Windows. It was really just meant as a starting point, so that v091 WIPs can flow starting from .00 with the new name (it overshadows bsnes v091, so publicly speaking this "shouldn't exist" and will probably be deleted from Google Code when v092 is ready.)
50 lines
1.4 KiB
C++
Executable File
50 lines
1.4 KiB
C++
Executable File
//PPUcounter emulates the H/V latch counters of the S-PPU2.
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//
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//real hardware has the S-CPU maintain its own copy of these counters that are
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//updated based on the state of the S-PPU Vblank and Hblank pins. emulating this
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//would require full lock-step synchronization for every clock tick.
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//to bypass this and allow the two to run out-of-order, both the CPU and PPU
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//classes inherit PPUcounter and keep their own counters.
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//the timers are kept in sync, as the only differences occur on V=240 and V=261,
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//based on interlace. thus, we need only synchronize and fetch interlace at any
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//point before this in the frame, which is handled internally by this class at
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//V=128.
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class PPUcounter {
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public:
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alwaysinline void tick();
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alwaysinline void tick(unsigned clocks);
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alwaysinline bool field () const;
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alwaysinline uint16 vcounter() const;
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alwaysinline uint16 hcounter() const;
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inline uint16 hdot() const;
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inline uint16 lineclocks() const;
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alwaysinline bool field (unsigned offset) const;
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alwaysinline uint16 vcounter(unsigned offset) const;
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alwaysinline uint16 hcounter(unsigned offset) const;
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inline void reset();
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function<void ()> scanline;
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void serialize(serializer&);
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private:
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inline void vcounter_tick();
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struct {
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bool interlace;
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bool field;
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uint16 vcounter;
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uint16 hcounter;
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} status;
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struct {
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bool field[2048];
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uint16 vcounter[2048];
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uint16 hcounter[2048];
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int32 index;
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} history;
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};
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