* Cells loaded from walk-data are half-transparent.
* The player symbol is half-transparent when showing different floors.
* Clear the texture before drawing a small map so that no garbage is
left when the drawing is clipped.
This one is used quite frequently in Sengoku Rance.
The implementation here is slightly wrong, in that the anchor point for
the pixel zoom is at the lop left of the screen instead of the center.
In OpenGL ES 3, glTexImage2D cannot handle GL_BGRA format. SDL_ttf
returns pixels in BGRA format (because it's the format used in
FreeType2), so it needs to be converted to RGBA before passing to
gfx_init_texture_with_pixels.
This adds `USE_GLES` compile-time flag. If it's defined, gfx_init()
requests an OpenGL ES >=3.0 context.
This also makes the following changes to make it work with OpenGL ES:
- The USE_GLES flag also switches shader's #version directive, which is
now provided separately from the .glsl file.
- Implicit conversion between int and float is not supported in GLSL ES.
- Use GL_RGB in gfx_copy_main_surface. Because main_surface is in GL_RGB
format, using GL_RGBA generates GL_INVALID_OPERATION in OpenGL ES.
Major differences from DrawDungeon.hll are:
- DGN, DTX, TES are loaded from individual files, not from a DLF archive
- 2D map functions are not used
- (unimplemented) Spinning motion of event markers
- (unimplemented) Additional 3D object types (polygon models and roofs)
It was introduced to flip texture image rendered by DrawDungeon when
presenting on the screen. In GALZOO this approach does not work because
dungeon texture is also used as the source image of gfx functions.
After this, DrawDungeon directly generates vertically flipped image, by
tweaking the projection matrix.
It should return the maximum Z value among all sprites, not among
visible sprites.
This fixes a bug in Rance VI where some UI elements are incorrectly
Z-ordered.
The parts list is now a tree, and only a single sprite is registered in
the global scene. GoatGUIEngine now manages rendering order of its own
sprites internally.
Before this, floating markers were rendered as OpenGL's point sprites.
But point sprites has an implementation-dependent maximum size, and
Intel driver's maximum (256 pixels) is too small for us.
After this, markers are drawn with the same shaders as normal objects,
using the billboarding technique.
Before this, all objects that share a texture were drawn at once.
Objects were not depth-sorted, so if a transparent object was drawn
first, objects behind it were not drawn.
After this, dungeon is drawn for each cell, sorted by distance from
the camera position. To reduce the number of cells to be drawn, PVS
(Potentially Visible Set) stored in dgn files is used.
kichikuou