From c2bb5bb61775e72b373b54aecbc6f5c33945f53f Mon Sep 17 00:00:00 2001
From: Tom <tom@raftt.io>
Date: Tue, 25 Oct 2022 19:51:53 +0300
Subject: [PATCH] (feat): Add option to set max FPS

Added the `WithMaxFPS` option to bubbletea program struct, if it is set
with a non 0 value it will set the maximum interval at which the view is
updated, if it is not set or set to 0, the interval will be the
`defaultFramerate` constant.
---
 options.go           | 12 ++++++++++++
 standard_renderer.go |  9 +++++++--
 tea.go               |  7 ++++++-
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/options.go b/options.go
index 30f7e6c..31c6612 100644
--- a/options.go
+++ b/options.go
@@ -3,6 +3,7 @@ package tea
 import (
 	"context"
 	"io"
+	"time"
 
 	"github.com/muesli/termenv"
 )
@@ -200,3 +201,14 @@ func WithFilter(filter func(Model, Msg) Msg) ProgramOption {
 		p.filter = filter
 	}
 }
+
+// WithMaxFPS sets a custom maximum FPS at which we should
+// update the view.
+func WithMaxFPS(fps uint) ProgramOption {
+	if fps > maxFPS {
+		fps = maxFPS
+	}
+	return func(p *Program) {
+		p.framerate = time.Second / time.Duration(fps)
+	}
+}
diff --git a/standard_renderer.go b/standard_renderer.go
index e4fb61c..6ec6873 100644
--- a/standard_renderer.go
+++ b/standard_renderer.go
@@ -17,6 +17,8 @@ const (
 	// defaultFramerate specifies the maximum interval at which we should
 	// update the view.
 	defaultFramerate = time.Second / 60
+
+	maxFPS = 120
 )
 
 // standardRenderer is a framerate-based terminal renderer, updating the view
@@ -54,12 +56,15 @@ type standardRenderer struct {
 
 // newRenderer creates a new renderer. Normally you'll want to initialize it
 // with os.Stdout as the first argument.
-func newRenderer(out *termenv.Output, useANSICompressor bool) renderer {
+func newRenderer(out *termenv.Output, useANSICompressor bool, framerate time.Duration) renderer {
+	if framerate == 0 {
+		framerate = defaultFramerate
+	}
 	r := &standardRenderer{
 		out:                out,
 		mtx:                &sync.Mutex{},
 		done:               make(chan struct{}),
-		framerate:          defaultFramerate,
+		framerate:          framerate,
 		useANSICompressor:  useANSICompressor,
 		queuedMessageLines: []string{},
 	}
diff --git a/tea.go b/tea.go
index ca24eac..13131c5 100644
--- a/tea.go
+++ b/tea.go
@@ -19,6 +19,7 @@ import (
 	"runtime/debug"
 	"sync"
 	"syscall"
+	"time"
 
 	"github.com/containerd/console"
 	isatty "github.com/mattn/go-isatty"
@@ -144,6 +145,10 @@ type Program struct {
 	windowsStdin *os.File //nolint:golint,structcheck,unused
 
 	filter func(Model, Msg) Msg
+
+	// framerate specifies a custom maximum interval at which we should
+	// update the view. If it is 0, the default value is used.
+	framerate time.Duration
 }
 
 // Quit is a special command that tells the Bubble Tea program to exit.
@@ -441,7 +446,7 @@ func (p *Program) Run() (Model, error) {
 
 	// If no renderer is set use the standard one.
 	if p.renderer == nil {
-		p.renderer = newRenderer(p.output, p.startupOptions.has(withANSICompressor))
+		p.renderer = newRenderer(p.output, p.startupOptions.has(withANSICompressor), p.framerate)
 	}
 
 	// Check if output is a TTY before entering raw mode, hiding the cursor and