From 18ea5681dee5bfaf021e2afe73843ddd01bde9bb Mon Sep 17 00:00:00 2001
From: Sasha Koshka <sashakoshka@tebibyte.media>
Date: Sun, 6 Nov 2022 12:42:22 -0500
Subject: [PATCH] Buffer is now drawn in the screen center (similar to kitty)

---
 application.go          |  6 +++---
 backends/pixel/pixel.go | 39 ++++++++++++++++++++++++++++++++-------
 2 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/application.go b/application.go
index c20ccef..80c8443 100644
--- a/application.go
+++ b/application.go
@@ -30,10 +30,10 @@ func (application *Application) Run (callback func (application *Application)) {
 
 	// TODO: load these from a file
 	application.config.colors = [4]color.Color {
-		color.RGBA { R: 0x81, G: 0xA1, B: 0xC1, A: 0xFF },
-		color.RGBA { R: 0x4C, G: 0x56, B: 0x6A, A: 0xFF },
-		color.RGBA { R: 0xD8, G: 0xDE, B: 0xE9, A: 0xFF },
 		color.RGBA { R: 0x2B, G: 0x30, B: 0x3C, A: 0xFF },
+		color.RGBA { R: 0x4C, G: 0x56, B: 0x6A, A: 0xFF },
+		color.RGBA { R: 0x2E, G: 0x34, B: 0x40, A: 0xFF },
+		color.RGBA { R: 0xA8, G: 0x55, B: 0x5D, A: 0xFF },
 	}
 	
 	application.config.padding = 4
diff --git a/backends/pixel/pixel.go b/backends/pixel/pixel.go
index 2eb3445..af08abb 100644
--- a/backends/pixel/pixel.go
+++ b/backends/pixel/pixel.go
@@ -23,6 +23,9 @@ type Backend struct {
 	metrics struct {
 		cellWidth  int
 		cellHeight int
+		padding    int
+		paddingX   int
+		paddingY   int
 	}
 }
 
@@ -125,7 +128,7 @@ func (backend *Backend) Resized () (resized bool) {
 func (backend *Backend) draw () {
 	// didDrawing := false
 	width, height := backend.application.Size()
-
+	
 	if backend.boundsDirty {
 		backend.window.Clear (
 			backend.config.Color(stone.ColorApplication))
@@ -155,6 +158,8 @@ func (backend *Backend) draw () {
 	}
 
 	backend.textDrawer.Clear()
+	backend.textDrawer.Color = 
+		backend.config.Color(stone.ColorForeground)
 	for x := 0; x < width; x ++ {
 		for y := 0; y < height; y ++ {
 			clean := backend.application.Clean(x, y)
@@ -165,7 +170,7 @@ func (backend *Backend) draw () {
 			content := cell.Rune()
 			if content < 32 { continue }
 			
-			//  draw cell
+			// draw cell
 			backend.textDrawer.Dot = backend.vectorAtPosition(x, y + 1)
 			backend.textDrawer.WriteRune(content)
 			backend.textDrawer.Draw(backend.window, pixel.IM)
@@ -190,17 +195,37 @@ func (backend *Backend) processEvents () {
 	backend.windowBounds = newBounds
 	
 	if backend.boundsDirty {
-		// TODO: set size of buffer
+		// calculate padding
+		backend.metrics.padding =
+			backend.config.Padding() *
+			backend.metrics.cellWidth
+		deadArea := float64(backend.metrics.padding * 2)
+
+		// calculate new width and height for buffer
+		width := int (
+			(backend.windowBounds.X - deadArea) /
+			float64(backend.metrics.cellWidth))
+		height := int (
+			(backend.windowBounds.Y - deadArea) /
+			float64(backend.metrics.cellHeight))
+		backend.application.SetSize(width, height)
+
+		// position buffer in center of screen
+		frameWidth  := width * backend.metrics.cellWidth
+		frameHeight := height * backend.metrics.cellHeight
+		backend.metrics.paddingX = (int(backend.windowBounds.X) - frameWidth)  / 2
+		backend.metrics.paddingY = (int(backend.windowBounds.Y) - frameHeight) / 2
 	}
 }
 
 func (backend *Backend) vectorAtPosition (x, y int) (vector pixel.Vec) {
-	padding := backend.config.Padding() * backend.metrics.cellWidth
-
 	vector = pixel.V (
-		float64 (x * backend.metrics.cellWidth + padding),
+		float64 (
+			x * backend.metrics.cellWidth +
+			backend.metrics.paddingX),
 		backend.windowBounds.Y - float64 (
-			y * backend.metrics.cellHeight + padding))
+			y * backend.metrics.cellHeight +
+			backend.metrics.paddingY))
 	return
 }