This adds a new texture memory allocation header,
texture_memory_alloc2.hpp, with two of each memory area.
This also adds two new examples, "cube_textured" and "cube_vq" that
demonstrate using the new texture_memory_alloc2 to perform CORE
rendering, geometry transformation, and tile acceleration
concurrently.
The previous texture_memory_alloc.hpp was written based on an
incorrect understanding of the "32-bit" and "64-bit" texture memory
address mapping.
The primary motivation is to rearrange the texture memory address map
so that "textures" (64-bit access) do not overlap with 32-bit
accesses, such as REGION_BASE or PARAM_BASE.
The serial_transfer loader, as long as the target program voluntarily
terminates itself at some point, is able to load multiple programs
consecutively without requiring a physical power cycle to reload the
transfer program from CD.
The current example.mk juggles between two different "memory layouts",
one for "burn to a physical CD" and another for "load via serial
cable". Because the serial_transfer program now relocates itself to
the end of system memory, this means the 0x8c010000 area is now usable
by programs that are loaded by serial_transfer.
This still has issues, notably:
Despite the first 16kbytes of audio being loaded prior to starting the
AICA ARM7 CPU, the GDROM drive returns "busy" for the following
~48kbytes. This in turn causes the AICA to play audio from
uninitialized memory.
There is also a separate issue where the timing of changing the start
address of the audio channel causes a faint popping sound throughout
the audio playback.
I should do more timing experiments with the GDROM drive, and improve
this example to play the audio with fewer artifacts.
This combines my iso9660 parsing code, with all of the prior gdrom packet
interface / command code.
The example, on real Dreamcast hardware, displays the first 2048 bytes [1] of every
file in the root directory on the serial console.
[1] or the size of the file, whichever is smaller
From the GCC manual.
> GCC permits a C structure to have no members:
struct empty {
};
> The structure has size zero. In C++, empty structures are part of the
> language. G++ treats empty structures as if they had a single member of type
> char.
I was not aware of the different behavior in C++.
This fixes every maple example--most were broken for multiple reasons, including
this one.
This also enables SH4 caching. This includes linking code/data into the P1
area (previously this was not the case).
The maple examples (which indeed involve much use of DMA) require much work to
successfully work with the operand and copyback caches. The vibration example
currently is the most complete, though I should consider more on how I want to
structure maple response operand cache invalidation more generally.
