From c82fd6aac7dc78fbdd0075937cf8bf8c80b265bb Mon Sep 17 00:00:00 2001
From: bloeys <bloeys@outlook.com>
Date: Mon, 4 Jul 2022 01:56:47 +0400
Subject: [PATCH] Correct alpha handling in glyph shader

---
 main.go                | 27 ++++++++++++---------------
 res/shaders/glyph.glsl |  6 ++----
 2 files changed, 14 insertions(+), 19 deletions(-)

diff --git a/main.go b/main.go
index e30d0f1..5451f39 100755
--- a/main.go
+++ b/main.go
@@ -10,10 +10,8 @@ import (
 	"github.com/bloeys/nmage/materials"
 	"github.com/bloeys/nmage/meshes"
 	"github.com/bloeys/nmage/renderer/rend3dgl"
-	"github.com/bloeys/nmage/timing"
 	nmageimgui "github.com/bloeys/nmage/ui/imgui"
 	"github.com/bloeys/nterm/glyphs"
-	"github.com/go-gl/gl/v4.1-core/gl"
 	"github.com/golang/freetype/truetype"
 	"github.com/veandco/go-sdl2/sdl"
 	"golang.org/x/image/font"
@@ -73,7 +71,6 @@ func main() {
 	})
 
 	//Don't flash white
-	gl.ClearColor(0, 0, 0, 0)
 	p.win.SDLWin.GLSwap()
 
 	engine.Run(p, p.win, p.imguiInfo)
@@ -156,12 +153,8 @@ func (p *program) Update() {
 	if input.KeyClicked(sdl.K_SPACE) {
 		p.shouldDrawGrid = !p.shouldDrawGrid
 	}
-
-	fmt.Println("FPS:", int(timing.GetAvgFPS()), "; Draws per frame:", charsPerFrame/16384)
 }
 
-const charsPerFrame = 100_000
-
 var xOff float32 = 0
 var yOff float32 = 0
 
@@ -172,8 +165,13 @@ var b = rand.Float32()
 func (p *program) Render() {
 
 	const colorSpd = 0.005
+	// const charsPerFrame = 100_000
 	defer p.GlyphRend.Draw()
 
+	if p.shouldDrawGrid {
+		p.drawGrid()
+	}
+
 	r += colorSpd
 	if r > 1 {
 		r = 0
@@ -190,17 +188,16 @@ func (p *program) Render() {
 	}
 
 	textColor := gglm.NewVec4(r, g, b, 1)
-
 	str := " ijojo\n\n Hello there, friend|. pq?\n ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	strLen := len(str)
 
-	for i := 0; i < charsPerFrame/strLen; i++ {
-		p.GlyphRend.DrawTextOpenGLAbs(str, gglm.NewVec3(xOff, float32(p.GlyphRend.Atlas.LineHeight)*5+yOff, 0), textColor)
-	}
+	p.GlyphRend.DrawTextOpenGLAbs(str, gglm.NewVec3(xOff, float32(p.GlyphRend.Atlas.LineHeight)*5+yOff, 0), textColor)
 
-	if p.shouldDrawGrid {
-		p.drawGrid()
-	}
+	// strLen := len(str)
+	// for i := 0; i < charsPerFrame/strLen; i++ {
+	// 	p.GlyphRend.DrawTextOpenGLAbs(str, gglm.NewVec3(xOff, float32(p.GlyphRend.Atlas.LineHeight)*5+yOff, 0), textColor)
+	// }
+
+	// fmt.Println("FPS:", int(timing.GetAvgFPS()), "; Draws per frame:", charsPerFrame/16384)
 }
 
 func (p *program) drawGrid() {
diff --git a/res/shaders/glyph.glsl b/res/shaders/glyph.glsl
index a3823f1..17bc197 100755
--- a/res/shaders/glyph.glsl
+++ b/res/shaders/glyph.glsl
@@ -29,7 +29,6 @@ void main()
 
     v2fUV0 = aUV0 + aVertPos.xy * sizeUV;
     v2fColor = aVertColor;
-    v2fFragPos = vec3(modelMat * vec4(aVertPos, 1.0));
 
     gl_Position = projViewMat * modelMat * vec4(aVertPos, 1.0);
 }
@@ -37,9 +36,8 @@ void main()
 //shader:fragment
 #version 410
 
-in vec4 v2fColor;
 in vec2 v2fUV0;
-in vec3 v2fFragPos;
+in vec4 v2fColor;
 
 out vec4 fragColor;
 
@@ -54,6 +52,6 @@ void main()
     // }
     // else
     {
-        fragColor = vec4(v2fColor.rgb, texColor.r);
+        fragColor = vec4(v2fColor.rgb, texColor.r*v2fColor.a);
     }
 }