* Change gint_inth_callback()
* Add intc_handler_function() to use C functions as handlers instead of
writing assembler, and use it in the RTC and USB
* Revisit the TMU handlers, which after moving out the callbacks, now
fit into 3 gates (great!), and adapt the ETMU handler
* Improve the timer driver (less code = better code, removed magic
constants assuming the VBR layout on SH3/SH4, etc.)
* Remove 2 gates and a gap from the compact scheme on SH3
* Define timer_configure() to replace timer_setup(), which could not be
cleanly updated to support GINT_CALL()
* Replace rtc_start/stop_timer with rtc_periodic_enable/disable, which
is less confusing because of ETMU being "RTC timers"
DGRAY_PUSH_ON/OFF will push the current gray engine state to a stack
before transitioning to on/off mode. DGRAY_POP will later recover the
saved state and transition back to it.
* Define dgray() to replace gray_start() and gray_stop()
* Introduce a mechanism to override the d*() functions rather than using
another set of functions, namely g*(). Gray rendering should now be
done with d*() (a compatibility macro for g*() is available until v2.1).
* Gray engine now reserves TMU0 at the start of the add-in to prevent
surprises if timers are exhausted, so it nevers fails to start
* Replace other gray engine functions with dgray_*()
* More general rendering functions (in render/) to lessen the burden of
porting them to the gray engine. As a consequence, dtext_opt(),
dprint_opt() and drect_border() are now available in the gray engine,
which was an omission from 230b796.
* Allow C_NONE in more functions, mainly on fx-CG 50
* Remove the now-unused dupdate_noint()
Since both platforms now have their VBR and gint-specific data loaded
along the add-in's data, the .gint.data section is entirely unused.
The .gint.bss section is still used for uninitialized objects (it has
different semantics than .bss which is initially cleared) and the
.gint.data.sh3 and .gint.bss.sh3 sections that are dropped on the
SH4-only fx-CG 50 are also still used.
This commit minimally changes the signature of timer_setup() to greatly
simplify timer management, allowing to user to let the library choose
available timers dynamically depending on the settings.
Gray quality is better on the Graph 35+E II, it still flickers a lot on
other models (as I remembered). There might be better settings out there
but I'm not sure we can reach the quality of the current Graph 35+E II
defaults. The Graph 75+E with which I tested might also be different
from other T6K11 such as the smaller Graph 35+E.
This macro used to protect the declaration of the [vram] variable of
gint. This variable was short to keep drawing functions short but could
clutter the namespace.
That being said, it's even better to just [#define vram gint_vram] if
you need. This change renames the variable to [gint_vram], exposes it
whenever <gint/display.h> is included, and removes the GINT_NEED_VRAM
macro altogether.