add preview for sample generation

src/app.zig

@@ -42,7 +42,7 @@ const FileChannel = struct {
     }
 };
 
-const DeviceChannel = struct {
+pub const DeviceChannel = struct {
     const ChannelName = std.BoundedArray(u8, NIDaq.max_channel_name_size + 1); // +1 for null byte
     const Direction = enum { input, output };
 
@@ -76,6 +76,20 @@ const DeviceChannel = struct {
     pub fn getChannelName(self: *DeviceChannel) [:0]const u8 {
         return utils.getBoundedStringZ(&self.channel_name);
     }
+
+    pub fn generateSine(samples: *std.ArrayList(f64), sample_rate: f64, frequency: f64, amplitude: f64) !void {
+        samples.clearRetainingCapacity();
+
+        const sample_count: usize = @intFromFloat(@ceil(sample_rate));
+        assert(sample_count >= 1);
+        try samples.ensureTotalCapacity(sample_count);
+
+        for (0..sample_count) |i| {
+            const i_f64: f64 = @floatFromInt(i);
+            const sample = std.math.sin(i_f64 / sample_rate * frequency * std.math.pi * 2) * amplitude;
+            samples.appendAssumeCapacity(sample);
+        }
+    }
 };
 
 pub const ChannelView = struct {
@@ -445,7 +459,7 @@ pub fn activateDeviceChannel(self: *App, channel_view: *ChannelView) !void {
         const task = try ni_daq.createTask(null);
         errdefer task.clear();
 
-        const sample_rate = device_channel.max_sample_rate;
+        const sample_rate = channel_view.sample_rate.?;
         try task.createAIVoltageChannel(.{
             .channel = device_channel.getChannelName(),
             .min_value = device_channel.min_value,
@@ -468,13 +482,10 @@ pub fn activateDeviceChannel(self: *App, channel_view: *ChannelView) !void {
         const task = try ni_daq.createTask(null);
         errdefer task.clear();
 
-        device_channel.write_pattern.clearAndFree();
-        try device_channel.write_pattern.appendNTimes(2, 1000);
-
         const write_pattern = device_channel.write_pattern.items;
         const samples_per_channel: u32 = @intCast(write_pattern.len);
 
-        const sample_rate = 5000; // device_channel.max_sample_rate;
+        const sample_rate = channel_view.sample_rate.?;
         try task.createAOVoltageChannel(.{
             .channel = device_channel.getChannelName(),
             .min_value = device_channel.min_value,
@@ -648,7 +659,7 @@ pub fn appendChannelFromDevice(self: *App, channel_name: []const u8) !void {
         .x_range = RangeF64.init(0, 0),
         .y_range = RangeF64.init(max_value, min_value),
         .source = .{ .device = device_channel_index },
-        .sample_rate = max_sample_rate,
+        .sample_rate = @min(max_sample_rate, 5000),
         .unit = unit
     });
     errdefer _ = self.channel_views.pop();

src/screens/main_screen.zig

@@ -47,6 +47,9 @@ protocol_modal: ?*ChannelView = null,
 frequency_input: UI.TextInputStorage,
 amplitude_input: UI.TextInputStorage,
 protocol_error_message: ?[]const u8 = null,
+protocol_graph_cache: Graph.Cache = .{},
+preview_samples: std.ArrayList(f64),
+preview_samples_y_range: RangeF64 = RangeF64.init(0, 0),
 
 pub fn init(app: *App) !MainScreen {
     const allocator = app.allocator;
@@ -54,10 +57,11 @@ pub fn init(app: *App) !MainScreen {
     var self = MainScreen{
         .app = app,
         .frequency_input = UI.TextInputStorage.init(allocator),
-        .amplitude_input = UI.TextInputStorage.init(allocator)
+        .amplitude_input = UI.TextInputStorage.init(allocator),
+        .preview_samples = std.ArrayList(f64).init(allocator)
     };
 
-    try self.frequency_input.setText("1000");
+    try self.frequency_input.setText("10");
     try self.amplitude_input.setText("10");
 
     return self;
@@ -66,6 +70,7 @@ pub fn init(app: *App) !MainScreen {
 pub fn deinit(self: *MainScreen) void {
     self.frequency_input.deinit();
     self.amplitude_input.deinit();
+    self.preview_samples.deinit();
 
     self.clearProtocolErrorMessage();
 }
@@ -697,6 +702,7 @@ fn showChannelView(self: *MainScreen, channel_view: *ChannelView, height: UI.Siz
 
 fn openProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
     self.protocol_modal = channel_view;
+    self.protocol_graph_cache.deinit();
 }
 
 fn closeModal(self: *MainScreen) void {
@@ -706,6 +712,8 @@ fn closeModal(self: *MainScreen) void {
 pub fn showProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
     var ui = &self.app.ui;
 
+    const device_channel = self.app.getChannelSourceDevice(channel_view).?;
+
     const container = ui.createBox(.{
         .key = ui.keyFromString("Protocol modal"),
         .background = srcery.black,
@@ -719,6 +727,25 @@ pub fn showProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
     container.beginChildren();
     defer container.endChildren();
 
+    {
+        const protocol_view = ui.createBox(.{
+            .key = ui.keyFromString("Protocol view"),
+            .size_x = UI.Sizing.initGrowFull(),
+            .size_y = UI.Sizing.initFixedPixels(ui.rem(4)),
+            .borders = UI.Borders.all(.{ .color = srcery.hard_black, .size = 2 })
+        });
+
+        const samples = self.preview_samples.items;
+        const view_rect = Graph.ViewOptions{
+            .x_range = RangeF64.init(0, @floatFromInt(samples.len)),
+            .y_range = self.preview_samples_y_range
+        };
+        Graph.drawCached(&self.protocol_graph_cache, protocol_view.persistent.size, view_rect, samples);
+        if (self.protocol_graph_cache.texture) |texture| {
+            protocol_view.texture = texture.texture;
+        }
+    }
+
     const FormInput = struct {
         name: []const u8,
         storage: *UI.TextInputStorage,
@@ -740,6 +767,7 @@ pub fn showProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
             .value = &amplitude
         },
     };
+    var any_input_modified = false;
 
     for (form_inputs) |form_input| {
         const label = form_input.name;
@@ -760,6 +788,35 @@ pub fn showProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
         label_box.alignment.y = .center;
 
         try ui.textInput(ui.keyFromString("Text input"), text_input_storage);
+
+        any_input_modified = any_input_modified or text_input_storage.modified;
+    }
+
+    if (any_input_modified) {
+        self.clearProtocolErrorMessage();
+
+        for (form_inputs) |form_input| {
+            const label = form_input.name;
+            const text_input_storage: *UI.TextInputStorage = form_input.storage;
+
+            const number = std.fmt.parseFloat(f32, text_input_storage.buffer.items) catch {
+                try self.setProtocolErrorMessage("ERROR: {s} must be a number", .{ label });
+                continue;
+            };
+
+            if (number <= 0) {
+                try self.setProtocolErrorMessage("ERROR: {s} must be positive", .{ label });
+                continue;
+            }
+
+            form_input.value.* = number;
+        }
+    }
+
+    if (self.protocol_error_message == null and any_input_modified) {
+        try App.DeviceChannel.generateSine(&self.preview_samples, channel_view.sample_rate.?, frequency, amplitude);
+        self.preview_samples_y_range = RangeF64.init(-amplitude*1.1, amplitude*1.1);
+        self.protocol_graph_cache.invalidate();
     }
 
     if (self.protocol_error_message) |message| {
@@ -792,26 +849,9 @@ pub fn showProtocolModal(self: *MainScreen, channel_view: *ChannelView) !void {
         btn.borders = UI.Borders.all(.{ .color = srcery.green, .size = 4 });
 
         if (ui.signal(btn).clicked() or ui.isKeyboardPressed(.key_enter)) {
-            self.clearProtocolErrorMessage();
-
-            for (form_inputs) |form_input| {
-                const label = form_input.name;
-                const text_input_storage: *UI.TextInputStorage = form_input.storage;
-
-                const number = std.fmt.parseFloat(f32, text_input_storage.buffer.items) catch {
-                    try self.setProtocolErrorMessage("ERROR: {s} must be a number", .{ label });
-                    continue;
-                };
-
-                if (number <= 0) {
-                    try self.setProtocolErrorMessage("ERROR: {s} must be positive", .{ label });
-                    continue;
-                }
-
-                form_input.value.* = number;
-            }
-
             if (self.protocol_error_message == null) {
+                try App.DeviceChannel.generateSine(&device_channel.write_pattern, channel_view.sample_rate.?, frequency, amplitude);
+
                 self.app.deferred_actions.appendAssumeCapacity(.{
                     .activate = channel_view
                 });

src/ui.zig

@@ -2014,6 +2014,7 @@ pub fn isCtrlDown(self: *UI) bool {
 pub const TextInputStorage = struct {
     buffer: std.ArrayList(u8),
 
+    modified: bool = false,
     editing: bool = false,
     last_pressed_at_ns: i128 = 0,
     cursor_start: usize = 0,
@@ -2032,11 +2033,15 @@ pub const TextInputStorage = struct {
     }
 
     pub fn setText(self: *TextInputStorage, text: []const u8) !void {
+        self.modified = true;
+
         self.buffer.clearAndFree();
         try self.buffer.appendSlice(text);
     }
 
     pub fn insertSingle(self: *TextInputStorage, index: usize, symbol: u8) !void {
+        self.modified = true;
+
         try self.buffer.insert(index, symbol);
 
         if (self.cursor_start >= index) {
@@ -2058,6 +2063,8 @@ pub const TextInputStorage = struct {
         const to_clamped   = std.math.clamp(to  , 0, self.buffer.items.len);
         if (from_clamped == to_clamped) return;
 
+        self.modified = true;
+
         const lower = @min(from_clamped, to_clamped);
         const upper = @max(from_clamped, to_clamped);
         assert(lower < upper);
@@ -2172,6 +2179,8 @@ pub const TextInputStorage = struct {
     fn insertMany(self: *TextInputStorage, index: usize, text: []const u8) !void {
         if (index > self.buffer.items.len) return;
 
+        self.modified = true;
+
         try self.buffer.insertSlice(index, text);
 
         if (self.cursor_start >= index) {
@@ -2184,6 +2193,10 @@ pub const TextInputStorage = struct {
     }
 };
 
+pub const TextInputResult = struct {
+    changed: bool = false
+};
+
 pub fn mouseTooltip(self: *UI) *Box {
     const tooltip = self.getBoxByKey(mouse_tooltip_box_key).?;