From a0bb0d0114c2b228f2f1715b6fc53d99901b0193 Mon Sep 17 00:00:00 2001
From: 3gg <3gg@shellblade.net>
Date: Sun, 29 Jun 2025 16:43:36 -0700
Subject: Add support for R8 linear textures to render baked AO

---
 src/asset/texture.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

(limited to 'src/asset/texture.c')

diff --git a/src/asset/texture.c b/src/asset/texture.c
index c790394..fb423cc 100644
--- a/src/asset/texture.c
+++ b/src/asset/texture.c
@@ -49,7 +49,7 @@ Texture* gfx_texture_load(GfxCore* gfxcore, const LoadTextureCmd* cmd) {
   assert(cmd->origin == AssetFromFile || cmd->origin == AssetFromMemory);
   assert(cmd->type == LoadTexture || cmd->type == LoadCubemap);
 
-  int            width, height, components, old_components;
+  int            width, height, components;
   unsigned char* pixels[6] = {0};
 
   switch (cmd->origin) {
@@ -64,7 +64,8 @@ Texture* gfx_texture_load(GfxCore* gfxcore, const LoadTextureCmd* cmd) {
       }
       break;
     }
-    case LoadCubemap:
+    case LoadCubemap: {
+      int old_components = 0;
       for (int i = 0; i < 6; ++i) {
         // Flip +Y and -Y textures vertically.
         stbi_set_flip_vertically_on_load(((i == 2) || (i == 3)) ? 1 : 0);
@@ -76,9 +77,10 @@ Texture* gfx_texture_load(GfxCore* gfxcore, const LoadTextureCmd* cmd) {
           log_error("Failed to load texture file: %s", filepath);
           break;
         }
-        if (i > 0 && components != old_components) {
-          log_error("All textures in a cubemap must have the same number of "
-                    "components");
+        if ((i > 0) && (components != old_components)) {
+          log_error(
+              "All textures in a cubemap must have the same number of "
+              "components");
           break;
         }
         if ((i != 2) && (i != 3)) {
@@ -89,6 +91,7 @@ Texture* gfx_texture_load(GfxCore* gfxcore, const LoadTextureCmd* cmd) {
       }
       break;
     }
+    }
     break;
   case AssetFromMemory:
     // TODO: Load textures from memory.
@@ -122,6 +125,25 @@ Texture* gfx_texture_load(GfxCore* gfxcore, const LoadTextureCmd* cmd) {
   }
 
   switch (components) {
+  case 1:
+    switch (cmd->colour_space) {
+    case LinearColourSpace:
+      desc.format = TextureR8;
+      break;
+    case sRGB:
+      // TODO: Gamma single-channel textures are not implemented yet.
+      //  The caller should convert the single-channel to RGB and pass it down
+      //  as sRGB. This is why the ChronographWatch currently appears red on the
+      //  back.
+      log_error("Gamma colour space is not supported for 1-channel textures");
+      // return 0;
+      desc.format = TextureR8;
+      break;
+    default:
+      log_error("Unsupported texture colour space: %d", cmd->colour_space);
+      return 0;
+    }
+    break;
   case 3:
     switch (cmd->colour_space) {
     case LinearColourSpace:
-- 
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