Implement SDF fonts. (#24)

* Initial SDF font generation work.

* Text now correctly displaying with proper spacing.

* Fix untextured draws, implement custom rectangles.

* Fix regular image display.

* Slightly refactor ImGui rendering.

* Implement outlines.

* Implement bevel.

* Create host device after loading the module if the installer wasn't run.

* Move ImGui files to its own folder.

* Fix outline sizes.

* Fix default ImGui font and font scales.

* Update font atlas files.

UnleashedRecomp/gpu/shader/imgui_common.hlsli

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "../imgui_common.h"
+#include "../imgui/imgui_common.h"
 
 struct PushConstants
 {
@@ -13,6 +13,7 @@ struct PushConstants
     float2 InverseDisplaySize;
     float2 Origin;
     float2 Scale;
+    float Outline;
 };
 
 Texture2D<float4> g_Texture2DDescriptorHeap[] : register(t0, space0);

UnleashedRecomp/gpu/shader/imgui_ps.hlsl

@@ -73,13 +73,67 @@ float4 PixelAntialiasing(float2 uvTexspace)
     return SampleLinear(uvTexspace);
 }
 
+float median(float r, float g, float b)
+{
+    return max(min(r, g), min(max(r, g), b));
+}
+
 float4 main(in Interpolators interpolators) : SV_Target
 {
     float4 color = interpolators.Color;
     color *= PixelAntialiasing(interpolators.Position.xy - 0.5);
     
     if (g_PushConstants.Texture2DDescriptorIndex != 0)
-        color *= g_Texture2DDescriptorHeap[g_PushConstants.Texture2DDescriptorIndex].Sample(g_SamplerDescriptorHeap[0], interpolators.UV);
+    {
+        Texture2D<float4> texture = g_Texture2DDescriptorHeap[g_PushConstants.Texture2DDescriptorIndex & 0x7FFFFFFF];
+        float4 textureColor = texture.Sample(g_SamplerDescriptorHeap[0], interpolators.UV);
+        
+        if ((g_PushConstants.Texture2DDescriptorIndex & 0x80000000) != 0)
+        {
+            uint width, height;
+            texture.GetDimensions(width, height);
+            
+            float pxRange = 8.0;
+            float2 unitRange = pxRange / float2(width, height);
+            float2 screenTexSize = 1.0 / fwidth(interpolators.UV);
+            float screenPxRange = max(0.5 * dot(unitRange, screenTexSize), 1.0);
+            
+            float sd = median(textureColor.r, textureColor.g, textureColor.b) - 0.5;
+            float screenPxDistance = screenPxRange * (sd + g_PushConstants.Outline / (pxRange * 2.0));
+            
+            if (g_PushConstants.ShaderModifier == IMGUI_SHADER_MODIFIER_TITLE_BEVEL)
+            {
+                float2 normal = normalize(float3(ddx(sd), ddy(sd), 0.01)).xy;
+                float3 rimColor = float3(1, 0.8, 0.29);
+                float3 shadowColor = float3(0.84, 0.57, 0);
+
+                float cosTheta = dot(normal, normalize(float2(1, 1)));
+                float3 gradient = lerp(color.rgb, cosTheta >= 0.0 ? rimColor : shadowColor, abs(cosTheta));
+                color.rgb = lerp(gradient, color.rgb, pow(saturate(sd + 0.8), 32.0));
+            }
+            else if (g_PushConstants.ShaderModifier == IMGUI_SHADER_MODIFIER_CATEGORY_BEVEL)
+            {
+                float2 normal = normalize(float3(ddx(sd), ddy(sd), 0.25)).xy;
+                float cosTheta = dot(normal, normalize(float2(1, 1)));
+                float gradient = 1.0 + cosTheta * 0.5;
+                color.rgb = saturate(color.rgb * gradient);
+            }
+            else if (g_PushConstants.ShaderModifier == IMGUI_SHADER_MODIFIER_TEXT_SKEW)
+            {
+                float2 normal = normalize(float3(ddx(sd), ddy(sd), 0.5)).xy;
+                float cosTheta = dot(normal, normalize(float2(1, 1)));
+                float gradient = saturate(1.0 + cosTheta);
+                color.rgb = lerp(color.rgb * gradient, color.rgb, pow(saturate(sd + 0.77), 32.0));
+            }
+
+            color.a *= saturate(screenPxDistance + 0.5);
+            color.a *= textureColor.a;
+        }
+        else
+        {
+            color *= textureColor;
+        }
+    }
     
     if (g_PushConstants.ShaderModifier == IMGUI_SHADER_MODIFIER_MARQUEE_FADE)
     {