Make JUTResFont load all texture data into one texture

Together with the previous change, this enables entire blocks of text to be rendered in one draw call.

libs/JSystem/include/JSystem/JUtility/JUTFont.h

@@ -7,8 +7,7 @@
 
 #if TARGET_PC
 struct FontDrawContext {
-    int loadedBlock = -1;
-    int loadedPage = -1;
+    bool isTextureLoaded = false;
 };
 #define FONT_DRAW_CTX , FontDrawContext* context
 #define FONT_DRAW_CTX_ARG , context

libs/JSystem/include/JSystem/JUtility/JUTResFont.h

@@ -18,10 +18,6 @@ struct BlockHeader {
     BE(u32) size;
 };
 
-#if TARGET_PC
-struct GlyphTextures;
-#endif
-
 /**
 * @ingroup jsystem-jutility
 * 
@@ -91,6 +87,16 @@ public:
     /* 0x66 */ u16 field_0x66;
     /* 0x68 */ u16 mMaxCode;
     /* 0x6C */ const IsLeadByte_func* mIsLeadByte;
+
+#if TARGET_PC
+    // Dusk change: we use a single large texture for all characters.
+    // This enables better draw call merging, ideally enabling entire blocks of
+    // text to be one draw call.
+    TGXTexObj mJoinedTextureObject;
+    u16 mJoinedTextureHeight;
+
+    void initJoinedTexture();
+#endif
 };
 
 extern u8 const JUTResFONT_Ascfont_fix12[];

libs/JSystem/src/JUtility/JUTResFont.cpp

@@ -6,26 +6,13 @@
 #include "JSystem/JUtility/JUTAssert.h"
 #include "JSystem/JUtility/JUTConsole.h"
 #include <gx.h>
-#include "absl/container/node_hash_map.h"
-
-#if TARGET_PC
-struct GlyphTextures {
-    absl::node_hash_map<int, TGXTexObj> textures;
-};
-#endif
 
 JUTResFont::JUTResFont() {
-#if TARGET_PC
-    mGlyphTextures = new GlyphTextures();
-#endif
     initialize_state();
     JUTFont::initialize_state();
 }
 
 JUTResFont::JUTResFont(const ResFONT* pFont, JKRHeap* pHeap) {
-#if TARGET_PC
-    mGlyphTextures = new GlyphTextures();
-#endif
     initialize_state();
     JUTFont::initialize_state();
     initiate(pFont, pHeap);
@@ -33,10 +20,7 @@ JUTResFont::JUTResFont(const ResFONT* pFont, JKRHeap* pHeap) {
 
 JUTResFont::~JUTResFont() {
 #if TARGET_PC
-    for (auto& pair : mGlyphTextures->textures) {
-        pair.second.reset();
-    }
-    delete mGlyphTextures;
+    mJoinedTextureObject.reset();
 #endif
 
     if (mValid) {
@@ -70,6 +54,33 @@ bool JUTResFont::initiate(const ResFONT* pFont, JKRHeap* pHeap) {
     return true;
 }
 
+#if TARGET_PC
+void JUTResFont::initJoinedTexture() {
+    if (mGly1BlockNum != 1) {
+        CRASH("mGly1BlockNum must be 1!");
+    }
+
+    const auto& block = *mpGlyphBlocks[0];
+    if (block.textureWidth % 8 != 0 || block.textureHeight % 8 != 0) {
+        // Idk how the GameCube's tiling texture format works so this is a safety check.
+        CRASH("Texture size not divisible!");
+    }
+
+    int pageCount = 0;
+    u32 pageNumCells = block.numRows * block.numColumns;
+    for (u32 code = block.startCode; code < block.endCode; code += pageNumCells) {
+        pageCount += 1;
+    }
+
+    mJoinedTextureHeight = block.textureHeight * pageCount;
+    GXInitTexObj(&mJoinedTextureObject, block.data, block.textureWidth,
+       mJoinedTextureHeight, static_cast<GXTexFmt>(block.textureFormat.host()),
+       GX_CLAMP, GX_CLAMP, false);
+
+    GXInitTexObjLOD(&mJoinedTextureObject, GX_LINEAR, GX_LINEAR, 0.0f, 0.0f, 0.0f, 0U, 0U, GX_ANISO_1);
+}
+#endif
+
 bool JUTResFont::protected_initiate(const ResFONT* pFont, JKRHeap* pHeap) {
     void** p;
     delete_and_initialize();
@@ -100,8 +111,10 @@ bool JUTResFont::protected_initiate(const ResFONT* pFont, JKRHeap* pHeap) {
         mpMapBlocks = JKR_NEW_ARRAY_ARGS(ResFONT::MAP1*, mMap1BlockNum, p);
     }
     setBlock();
-    return true;
 
+    IF_DUSK(initJoinedTexture());
+
+    return true;
 }
 
 void JUTResFont::countBlock() {
@@ -258,8 +271,13 @@ f32 JUTResFont::drawChar_scale(f32 pos_x, f32 pos_y, f32 scale_x, f32 scale_y, i
     f32 y2 = getDescent() * (scale_y / getHeight()) + pos_y;
 
     u16 texW  = mpGlyphBlocks[field_0x66]->textureWidth;
+#if TARGET_PC
+    u16 texH  = mJoinedTextureHeight;
+#else
     u16 texH  = mpGlyphBlocks[field_0x66]->textureHeight;
+#endif
     u16 cellW = mpGlyphBlocks[field_0x66]->cellWidth;
+
     u16 cellH = mpGlyphBlocks[field_0x66]->cellHeight;
     s32 u1 = (mWidth * 0x8000) / texW;
     s32 v1 = (mHeight * 0x8000) / texH;
@@ -456,26 +474,12 @@ void JUTResFont::loadImage(int code, GXTexMapID id FONT_DRAW_CTX){
         mHeight = cellRow * cellH;
 
 #if TARGET_PC
-        if (!context || context->loadedPage != pageIdx || context->loadedBlock != i) {
-            const auto found = mGlyphTextures->textures.find(pageIdx);
-            GXTexObj* texObj;
-            if (found == mGlyphTextures->textures.end()) {
-                texObj = &mGlyphTextures->textures[pageIdx];
-                void* pImg = &mpGlyphBlocks[i]->data[pageIdx * mpGlyphBlocks[i]->textureSize];
-                GXInitTexObj(texObj, pImg, mpGlyphBlocks[i]->textureWidth,
-                             mpGlyphBlocks[i]->textureHeight, (GXTexFmt)(u16)mpGlyphBlocks[i]->textureFormat,
-                             GX_CLAMP, GX_CLAMP, 0);
-
-                GXInitTexObjLOD(texObj, GX_LINEAR, GX_LINEAR, 0.0f, 0.0f, 0.0f, 0U, 0U, GX_ANISO_1);
-            } else {
-                texObj = &found->second;
-            }
-
-            GXLoadTexObj(texObj, id);
+        mHeight += texH * pageIdx;
 
+        if (!context || !context->isTextureLoaded) {
+            GXLoadTexObj(&mJoinedTextureObject, id);
             if (context) {
-                context->loadedBlock = i;
-                context->loadedPage = pageIdx;
+                context->isTextureLoaded = true;
             }
         }