From 6c22b58487a47d0c40dadcde085c648c331d99a7 Mon Sep 17 00:00:00 2001
From: skymz4 <99190689+skymz4@users.noreply.github.com>
Date: Sat, 23 Apr 2022 14:54:10 +0200
Subject: [PATCH] __

---
 renderd7.cpp | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/renderd7.cpp b/renderd7.cpp
index 01e49cd..03589cb 100644
--- a/renderd7.cpp
+++ b/renderd7.cpp
@@ -950,6 +950,72 @@ void RenderD7::Image::LoadPFromBuffer(const std::vector<u8> &buffer)
 	}
 }
 
+static u32 GetNextPowerOf2(u32 v) {
+    v--;
+    v |= v >> 1;
+    v |= v >> 2;
+    v |= v >> 4;
+    v |= v >> 8;
+    v |= v >> 16;
+    v++;
+    return (v >= 64 ? v : 64);
+}
+
+static bool C3DTexToC2DImage(C2D_Image *texture, u32 width, u32 height, u8 *buf) {
+    if (width >= 1024 || height >= 1024)
+        return false;
+    
+    C3D_Tex *tex = new C3D_Tex[sizeof(C3D_Tex)];
+    Tex3DS_SubTexture *subtex = new Tex3DS_SubTexture[sizeof(Tex3DS_SubTexture)];
+    subtex->width = static_cast<u16>(width);
+    subtex->height = static_cast<u16>(height);
+    // RGBA -> ABGR
+    for (u32 row = 0; row < subtex->width; row++) {
+        for (u32 col = 0; col < subtex->height; col++) {
+            u32 z = (row + col * subtex->width) * BYTES_PER_PIXEL;
+            
+            u8 r = *(u8 *)(buf + z);
+            u8 g = *(u8 *)(buf + z + 1);
+            u8 b = *(u8 *)(buf + z + 2);
+            u8 a = *(u8 *)(buf + z + 3);
+            
+            *(buf + z) = a;
+            *(buf + z + 1) = b;
+            *(buf + z + 2) = g;
+            *(buf + z + 3) = r;
+        }
+    }
+    
+    u32 w_pow2 = GetNextPowerOf2(subtex->width);
+    u32 h_pow2 = GetNextPowerOf2(subtex->height);
+    subtex->left = 0.f;
+    subtex->top = 1.f;
+    subtex->right = (subtex->width /static_cast<float>(w_pow2));
+    subtex->bottom = (1.0 - (subtex->height / static_cast<float>(h_pow2)));
+    C3D_TexInit(tex, static_cast<u16>(w_pow2), static_cast<u16>(h_pow2), GPU_RGBA8);
+    C3D_TexSetFilter(tex, GPU_NEAREST, GPU_NEAREST);
+    
+    std::memset(tex->data, 0, tex->size);
+    
+    for (u32 x = 0; x < subtex->width; x++) {
+        for (u32 y = 0; y < subtex->height; y++) {
+            u32 dst_pos = ((((y >> 3) * (w_pow2 >> 3) + (x >> 3)) << 6) + ((x & 1) | ((y & 1) << 1) | ((x & 2) << 1) | ((y & 2) << 2) | ((x & 4) << 2) | ((y & 4) << 3))) * BYTES_PER_PIXEL;
+            u32 src_pos = (y * subtex->width + x) * BYTES_PER_PIXEL;
+            std::memcpy(&(static_cast<u8 *>(tex->data))[dst_pos], &(static_cast<u8 *>(buf))[src_pos], BYTES_PER_PIXEL);
+        }
+    }
+    
+    C3D_TexFlush(tex);
+    tex->border = RenderD7::Color::Hex("#000000", 0);
+    C3D_TexSetWrap(tex, GPU_CLAMP_TO_BORDER, GPU_CLAMP_TO_BORDER);
+    if (tex && subtex) {
+        texture->tex = tex;
+        texture->subtex = subtex;
+        return true;
+    }
+    return false;
+}
+
 void RenderD7::Image::FromSheet(RenderD7::Sheet sheet, size_t index)
 {