Super simple version of optimized text rendering done

2 files changed, 15 insertions, 8 deletions

diff --git a/source/shaders/ui_text_shader.fs.glsl b/source/shaders/ui_text_shader.fs.glsl
index d8bdcfb..bca9f7a 100644
--- a/source/shaders/ui_text_shader.fs.glsl
+++ b/source/shaders/ui_text_shader.fs.glsl
@@ -1,12 +1,16 @@
 #version 330 core
 
 in vec2 TexCoords;
-uniform sampler2D Texture;
+flat in int Index;
+uniform sampler2DArray TextureAtlas;
+uniform int TextureMap[32];
 uniform vec3 TextColor;
 out vec4 FragColor;
 
 void main() {
-  vec4 sampled = vec4(1.0, 1.0, 1.0, texture(Texture, TexCoords));
-  FragColor = sampled * vec4(TextColor, 1.0);
+  int TextureId = TextureMap[Index];
+  vec3 TextureIndexCoords = vec3(TexCoords.xy, TextureId);
+  vec4 sampled = vec4(1.0, 1.0, 1.0, texture(TextureAtlas, TextureIndexCoords).r);
+  FragColor = sampled * vec4(TextColor, 1);
 };
 
diff --git a/source/shaders/ui_text_shader.vs.glsl b/source/shaders/ui_text_shader.vs.glsl
index ecaefa4..363833e 100644
--- a/source/shaders/ui_text_shader.vs.glsl
+++ b/source/shaders/ui_text_shader.vs.glsl
@@ -1,12 +1,15 @@
 #version 330 core
-layout(location=0) in vec3 aPos;
-layout(location=1) in vec2 aTex;
+layout(location=0) in vec2 aPos;
 
 uniform mat4 Projection;
-
+uniform mat4 LetterTransforms[32];
 out vec2 TexCoords;
+flat out int Index;
 
 void main() {
-  gl_Position = Projection * vec4(aPos, 1.0);
-  TexCoords = aTex;
+  gl_Position = Projection * LetterTransforms[gl_InstanceID] * vec4(aPos, 0.0, 1.0);
+  vec2 tex = aPos;
+  TexCoords = tex;
+  TexCoords.y = 1.0 - TexCoords.y;
+  Index = gl_InstanceID;
 }