Text wrapping; basic scrolling in DocumentWidget

3 files changed, 81 insertions, 36 deletions

diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index c0dbcded..7fe30f1e 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -25,6 +25,7 @@ struct Impl_DocumentWidget {
     iString *newSource;
     iGmDocument *doc;
     int pageMargin;
+    int scrollY;
 };
 
 iDeclareType(Url)
@@ -71,6 +72,7 @@ void init_DocumentWidget(iDocumentWidget *d) {
     d->newSource = new_String();
     d->doc = new_GmDocument();
     d->pageMargin = 5;
+    d->scrollY = 0;
     setUrl_DocumentWidget(d, collectNewCStr_String("file:///home/jaakko/test.gmi"));
 }
 
@@ -173,13 +175,18 @@ static iBool processEvent_DocumentWidget_(iDocumentWidget *d, const SDL_Event *e
             return iTrue;
         }
     }
+    else if (ev->type == SDL_MOUSEWHEEL) {
+        d->scrollY -= 3 * ev->wheel.y * lineHeight_Text(default_FontId);
+        postRefresh_App();
+        return iTrue;
+    }
     return processEvent_Widget(w, ev);
 }
 
 iDeclareType(DrawContext)
 
 struct Impl_DrawContext {
-    const iDocumentWidget *d;
+    const iDocumentWidget *widget;
     iRect bounds;
     iPaint paint;
 };
@@ -189,8 +196,9 @@ static void drawRun_DrawContext_(void *context, const iGmRun *run) {
     iString text;
     /* TODO: making a copy is unnecessary; the text routines should accept Rangecc */
     initRange_String(&text, run->text);
-    drawString_Text(run->font, add_I2(d->bounds.pos, run->bounds.pos), run->color, &text);
-    drawRect_Paint(&d->paint, moved_Rect(run->bounds, d->bounds.pos), red_ColorId);
+    iInt2 origin = addY_I2(d->bounds.pos, -d->widget->scrollY);
+    drawString_Text(run->font, add_I2(run->bounds.pos, origin), run->color, &text);
+//    drawRect_Paint(&d->paint, moved_Rect(run->bounds, origin), red_ColorId);
     deinit_String(&text);
 }
 
@@ -206,11 +214,14 @@ static void draw_DocumentWidget_(const iDocumentWidget *d) {
         iConstCast(iDocumentWidget *, d)->state = ready_DocumentState;
     }
     if (d->state != ready_DocumentState) return;
-    iDrawContext ctx = {.d = d, .bounds = bounds_Widget(w) };
+    iDrawContext ctx = {.widget = d, .bounds = bounds_Widget(w) };
     shrink_Rect(&ctx.bounds, init1_I2(gap_UI * d->pageMargin));
     init_Paint(&ctx.paint);
     drawRect_Paint(&ctx.paint, ctx.bounds, teal_ColorId);
-    render_GmDocument(d->doc, (iRangei){ 0, height_Rect(ctx.bounds) }, drawRun_DrawContext_, &ctx);
+    render_GmDocument(d->doc,
+                      (iRangei){ d->scrollY, d->scrollY + height_Rect(ctx.bounds) },
+                      drawRun_DrawContext_,
+                      &ctx);
 }
 
 iBeginDefineSubclass(DocumentWidget, Widget)
diff --git a/src/ui/text.c b/src/ui/text.c
index 23e28e4d..afad778c 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -15,6 +15,7 @@
 #include <the_Foundation/vec2.h>
 
 #include <SDL_surface.h>
+#include <SDL_hints.h>
 #include <stdarg.h>
 
 iDeclareType(Glyph)
@@ -115,12 +116,12 @@ void init_Text(SDL_Renderer *render) {
     /* Load the fonts. */ {
         const struct { const iBlock *ttf; int size; } fontData[max_FontId] = {
             { &fontFiraSansRegular_Embedded, fontSize_UI },
-            { &fontFiraMonoRegular_Embedded, fontSize_UI },
+            { &fontFiraMonoRegular_Embedded, fontSize_UI * 0.85f },
             { &fontFiraSansRegular_Embedded, fontSize_UI * 1.5f },
             { &fontFiraSansLightItalic_Embedded, fontSize_UI },
             { &fontFiraSansBold_Embedded, fontSize_UI },
-            { &fontFiraSansBold_Embedded, fontSize_UI * 1.5f },
-            { &fontFiraSansBold_Embedded, fontSize_UI * 1.75f },
+            { &fontFiraSansBold_Embedded, fontSize_UI * 1.35f },
+            { &fontFiraSansBold_Embedded, fontSize_UI * 1.7f },
             { &fontFiraSansBold_Embedded, fontSize_UI * 2.0f },
         };
         iForIndices(i, fontData) {
@@ -377,18 +378,26 @@ static iChar nextChar_(const char **chPos, const char *end) {
 }
 
 static iInt2 run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLen, iInt2 pos,
-                       int *runAdvance_out) {
+                       int xposLimit, const char **continueFrom_out, int *runAdvance_out) {
     iInt2 size = zero_I2();
     const iInt2 orig = pos;
     const stbtt_fontinfo *info = &d->font;
     float xpos = pos.x;
     float xposMax = xpos;
+    iAssert(xposLimit == 0 || mode == measure_RunMode);
+    const char *lastWordEnd = text.start;
+    if (continueFrom_out) {
+        *continueFrom_out = text.end;
+    }
+    iChar prevCh = 0;
     for (const char *chPos = text.start; chPos != text.end; ) {
+        iAssert(chPos < text.end);
         iChar ch = nextChar_(&chPos, text.end);
         /* Special instructions. */ {
             if (ch == '\n') {
                 xpos = pos.x;
                 pos.y += d->height;
+                prevCh = ch;
                 continue;
             }
             if (ch == '\r') {
@@ -397,20 +406,26 @@ static iInt2 run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
                 if (mode == draw_RunMode) {
                     SDL_SetTextureColorMod(text_.cache, clr.r, clr.g, clr.b);
                 }
+                prevCh = 0;
                 continue;
             }
         }
         const iGlyph *glyph = glyph_Font_(d, ch);
-        int x1 = iRound(xpos);
-        int x2 = x1 + glyph->rect.size.x;
+        float x1 = xpos;
+        float x2 = x1 + glyph->rect.size.x;
+        if (xposLimit > 0 && x2 > xposLimit) {
+            /* Out of space. */
+            *continueFrom_out = lastWordEnd;
+            break;
+        }
         size.x = iMax(size.x, x2 - orig.x);
         size.y = iMax(size.y, pos.y + d->height - orig.y);
         if (mode != measure_RunMode) {
-            SDL_Rect dst = { x1 + glyph->dx,
-                             pos.y + d->baseline + glyph->dy,
-                             glyph->rect.size.x,
-                             glyph->rect.size.y };
-            SDL_RenderCopy(text_.render, text_.cache, (const SDL_Rect *) &glyph->rect, &dst);
+            SDL_FRect dst = { x1 + glyph->dx,
+                              pos.y + d->baseline + glyph->dy,
+                              glyph->rect.size.x,
+                              glyph->rect.size.y };
+            SDL_RenderCopyF(text_.render, text_.cache, (const SDL_Rect *) &glyph->rect, &dst);
         }
         int advance, lsb;
         const iBool spec = isSpecialChar_(ch);
@@ -420,6 +435,9 @@ static iInt2 run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
         }
         xpos += d->scale * advance;
         xposMax = iMax(xposMax, xpos);
+        if (!isSpace_Char(prevCh) && isSpace_Char(ch)) {
+            lastWordEnd = chPos;
+        }
         /* Check the next character. */ {
             /* TODO: No need to decode the next char twice; check this on the next iteration. */
             const char *peek = chPos;
@@ -428,6 +446,7 @@ static iInt2 run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
                 xpos += d->scale * stbtt_GetCodepointKernAdvance(info, ch, next);
             }
         }
+        prevCh = ch;
         if (--maxLen == 0) {
             break;
         }
@@ -446,44 +465,56 @@ iInt2 measure_Text(int fontId, const char *text) {
     if (!*text) {
         return init_I2(0, lineHeight_Text(fontId));
     }
-    return run_Font_(
-        &text_.fonts[fontId], measure_RunMode, range_CStr(text), iInvalidSize, zero_I2(), NULL);
+    return run_Font_(&text_.fonts[fontId],
+                     measure_RunMode,
+                     range_CStr(text),
+                     iInvalidSize,
+                     zero_I2(),
+                     0,
+                     NULL,
+                     NULL);
 }
 
-iInt2 advance_Text(int fontId, const char *text) {
+iInt2 advanceRange_Text(int fontId, iRangecc text) {
     int advance;
     const int height = run_Font_(&text_.fonts[fontId],
                                  measure_RunMode,
-                                 range_CStr(text),
+                                 text,
                                  iInvalidSize,
                                  zero_I2(),
+                                 0,
+                                 NULL,
                                  &advance)
                            .y;
     return init_I2(advance, height);
 }
 
-iInt2 advanceN_Text(int fontId, const char *text, size_t n) {
-    if (n == 0) {
-        return init_I2(0, lineHeight_Text(fontId));
-    }
+iInt2 tryAdvanceRange_Text(int fontId, iRangecc text, int width, const char **endPos) {
     int advance;
-    run_Font_(&text_.fonts[fontId], measure_RunMode, range_CStr(text), n, zero_I2(), &advance);
-    return init_I2(advance, lineHeight_Text(fontId));
+    const int height = run_Font_(&text_.fonts[fontId],
+                                 measure_RunMode,
+                                 text,
+                                 iInvalidSize,
+                                 zero_I2(),
+                                 width,
+                                 endPos,
+                                 &advance)
+                           .y;
+    return init_I2(advance, height);
 }
 
-iInt2 advanceRange_Text(int fontId, iRangecc text) {
-    /* TODO: Rangecc should be the default for runs; no need to copy here */
-    iString str;
-    initRange_String(&str, text);
-    const iInt2 metrics = advance_Text(fontId, cstr_String(&str));
-    deinit_String(&str);
-    return metrics;
+iInt2 advance_Text(int fontId, const char *text) {
+    return advanceRange_Text(fontId, range_CStr(text));
 }
 
-iInt2 tryAdvanceRange_Text(int fontId, iRangecc text, int width, const char **endPos) {
+iInt2 advanceN_Text(int fontId, const char *text, size_t n) {
+    if (n == 0) {
+        return init_I2(0, lineHeight_Text(fontId));
+    }
     int advance;
-    const int height = run_Font_(&text_.fonts[fontId], measure_RunMode, text, iInvalidSize, zero_I2(), &advance).y;
-
+    run_Font_(
+        &text_.fonts[fontId], measure_RunMode, range_CStr(text), n, zero_I2(), 0, NULL, &advance);
+    return init_I2(advance, lineHeight_Text(fontId));
 }
 
 static void draw_Text_(int fontId, iInt2 pos, int color, iRangecc text) {
@@ -495,6 +526,8 @@ static void draw_Text_(int fontId, iInt2 pos, int color, iRangecc text) {
               text,
               iInvalidSize,
               pos,
+              0,
+              NULL,
               NULL);
 }
 
diff --git a/src/ui/text.h b/src/ui/text.h
index 9bf69c80..ddf9da86 100644
--- a/src/ui/text.h
+++ b/src/ui/text.h
@@ -42,6 +42,7 @@ iInt2   measure_Text        (int fontId, const char *text);
 iInt2   advance_Text        (int fontId, const char *text);
 iInt2   advanceN_Text       (int fontId, const char *text, size_t n); /* `n` in characters */
 iInt2   advanceRange_Text   (int fontId, iRangecc text);
+iInt2   tryAdvanceRange_Text(int fontId, iRangecc text, int width, const char **endPos);
 
 void    draw_Text           (int fontId, iInt2 pos, int color, const char *text, ...); /* negative pos to switch alignment */
 void    drawString_Text     (int fontId, iInt2 pos, int color, const iString *text);