VampireSurvivors/src/system/frame.zig
2026-07-14 14:14:27 +01:00

132 lines
4.4 KiB
Zig

//! ----------------------------------------------------
//! ----------------------------------------------------
const std = @import("std");
const sdl = @import("sdl");
const gtl = @import("gtl");
const App = @import("app");
const component = @import("../component/root.zig");
const resource = @import("../resource/root.zig");
const event = @import("../event/root.zig");
/// ----------------------------------------------------
/// ----------------------------------------------------
pub fn beginFrame(ctx: App.scheduler.Context) !void {
const res = try ctx.app.resources.getMany(struct {
window: *resource.Window,
frame: *resource.Frame,
time: *resource.Time,
textures: *resource.Textures,
renderer: *resource.Renderer,
});
//
// TIME
//
res.time.last = res.time.now;
res.time.now = sdl.SDL_GetPerformanceCounter();
res.time.dt =
@as(f32, @floatFromInt(res.time.now - res.time.last)) /
@as(f32, @floatFromInt(res.time.frequency));
//
// CAMERA
//
var target_transform: ?*const component.Transform = null;
{ // GATHER CAMERAS TARGET
var query = ctx.app.world.query(struct {
transform: *component.Transform,
camera_target: ?*component.CameraTarget,
}, .{});
while (query.next()) |e| {
if (e.camera_target) |_| {
target_transform = e.transform;
}
}
}
{ // GATHER CAMERAS
var query = ctx.app.world.query(struct {
camera: *component.Camera,
transform: *component.Transform,
}, .{});
while (query.next()) |e| {
const window_width: f32 = @floatFromInt(res.window.width);
const window_height: f32 = @floatFromInt(res.window.height);
const target = if (target_transform) |v| v else continue;
e.transform.pos[0] += ((window_width / 2.0) - (target.pos[0] + target.size[0] / 2.0) - e.transform.pos[0]) / 20.0;
e.transform.pos[1] += ((window_height / 2.0) - (target.pos[1] + target.size[1] / 2.0) - e.transform.pos[1]) / 20.0;
// --- SET CURRENT FRAME CAMERA ---
res.frame.camera = .{
.value = e.camera,
.transform = e.transform,
};
}
}
{ // BUILD TEXTURES
for (res.textures.data.items()) |*entry| {
// --- SKIP IF ALREADY BUILD ---
if (entry.value.raw != null) continue;
// --- SURFACE ---
const surface = sdl.IMG_Load(entry.value.path.ptr) orelse {
gtl.log.err("Texture: {s}", .{sdl.SDL_GetError()});
continue;
};
defer sdl.SDL_DestroySurface(surface);
// --- TEXTURE ---
const raw = sdl.SDL_CreateTextureFromSurface(
res.renderer.raw,
surface,
) orelse return error.Texture;
// --- SET TEXTURE FILTER ---
_ = sdl.SDL_SetTextureScaleMode(
raw,
sdl.SDL_SCALEMODE_PIXELART,
);
// --- ASSIGN ---
entry.value.raw = raw;
entry.value.size = .{ raw.*.w, raw.*.h };
// --- DEBUG ---
std.debug.print("{s}┏━ TEXTURE{s}\n", .{ gtl.ansi.purple, gtl.ansi.reset });
std.debug.print("{s}┃{s} Path: \"{s}\"\n", .{ gtl.ansi.purple, gtl.ansi.reset, entry.value.path });
std.debug.print("{s}┃{s} Size: {}x{}\n", .{ gtl.ansi.purple, gtl.ansi.reset, raw.*.w, raw.*.h });
std.debug.print("{s}┃{s} Filter: PixelArt\n", .{ gtl.ansi.purple, gtl.ansi.reset });
std.debug.print("{s}┗━{s}\n", .{ gtl.ansi.purple, gtl.ansi.reset });
}
}
}
/// ----------------------------------------------------
/// ----------------------------------------------------
pub fn endFrame(ctx: App.scheduler.Context) !void {
const res = try ctx.app.resources.getMany(struct {
frame: *resource.Frame,
time: *resource.Time,
});
res.frame.camera = null;
res.time.elapsed += res.time.dt;
const frame_time =
@as(f32, @floatFromInt(sdl.SDL_GetPerformanceCounter() - res.time.now)) /
@as(f32, @floatFromInt(res.time.frequency));
if (frame_time < res.time.target_dt) {
const delay_ms = (res.time.target_dt - frame_time) * 1000.0;
sdl.SDL_Delay(@intFromFloat(delay_ms));
}
}