DrawField is a variant of DrawDungeon. Unlike the first-person
perspective of DrawDungeon, DrawField uses a third-person, bird's-eye
view camera.
Key features include:
- Character Rendering: A new system to render up to 256 billboarded
sprites (characters, enemies, etc.) in the 3D world. The renderer
supports controlling position, sprite animation, and visibility for
each character.
- DrawField HLL API: Functions for loading assets, managing characters,
and manipulating dungeon properties like door locks.
- Renderer: The core renderer is updated to support the DrawField mode.
This includes disabling fog, handling sprite sheets via UV
manipulation, and rendering ceilings as billboards.
- Map: The 2D map has been updated to reflect the DrawField style,
including colored door lock indicators.
* dtx_load_from_dtl() loads lightmap textures.
* dgn_calc_lightmap() calculates lightmap texture index for each cell
based on the state of the surrounding walls.
Early versions of System4 (Sys42VM.dll < 3.0) execute destructors for
global variables on exit.
Dungeons & Dolls saves its game state in the destructors of global
variables (~CDataDoll(), ~CDataItem(), ~CDataMain()), so the game was
not saved in xsystem4 before this.
This behavior has some quirks:
* Destructors for variables on the call stack are not called on exit.
* Destructors are called in the reverse order of the global variable
declarations.
* Inside a destructor, it is possible to access another global variable
whose destructor has already been called (!).
Since this is a problematic behavior that was removed in later versions
of Sys42VM, let's add minimal support for it as a game-specific hack.
Following the implementation of `logs` (#220), `scenes` is now also
implemented as a circular buffer. This ensures that when the number of
saved scenes reaches a certain limit (500), the oldest scenes are
automatically discarded.
Texture.dtl contains multiple sets of wall, floor, and ceiling texture
images. dtx_load_from_dtl() randomly selects a texture set using the
floor number as the random seed and returns it as a dtx structure.
In DrawDungeon2, dungeons are generated randomly using a dedicated
random number generator (mtrand43.c), which is a Mersenne Twister with
N=4, M=3.
The entry point for map generation is dgn_generate_drawdungeon2(),
which deterministically generates a floor map using the floor number as
the random seed.
I verified that generated floor layout, player starting position,
exit, and treasure chest locations match the original DrawDungeon2.dll
up to the 1000th floor.
Some classes in Dungeons & Dolls serialize themselves using
`File.Write(this)` in their destructors. Because `File.Write` takes the
argument by value, a copy of `this` is created. If the destructor is
called on the copied `this`, it falls into an an infinite loop.
It provides 64-bit calculation functions with virtual registers.
While the original CalcTable.dll accumulates instructions and executes
them with CalcTable.Run(), this implementation performs calculations on
the fly. This simplification is possible because Run() is only called
with loop=1.
`system.Error()` is used for critical errors, so its message should be
presented to the user.
This makes system.Error() show a message box, allowing users to choose
between stopping execution or continuing.
This fixes https://github.com/kichikuou/xsystem4-android/issues/14.
There appears to be a bug in the OpenGL ES implementation for PowerVR
that prevents row_major mat4x3 uniforms from loading correctly.
This changes bone_matrices from row_major mat4x3 to column_major mat3x4
and transposes them manually in the vertex shaders. (Column major mat4x3
cannot be used due to the UBO size limitation)
The `defines` string in load_shader() is prepended to the glsl file, but
it was not terminated with a newline, so the resulting shader source
looked like this:
#define REIGN_ENGINE 0
#define TAPIR_ENGINE 1
#define ENGINE 1/* Copyright (C) ...
*
* This program is free software; ...
...
This confused some OpenGL ES implementations, causing a syntax error.
https://github.com/kichikuou/xsystem4-android/issues/15
brombrom-hani