5 files changed, 96 insertions, 50 deletions

diff --git a/src/app.c b/src/app.c
index ba282440..54f35373 100644
--- a/src/app.c
+++ b/src/app.c
@@ -129,7 +129,7 @@ struct Impl_App {
     iTime        lastDropTime; /* for detecting drops of multiple items */
     int          autoReloadTimer;
     iPeriodic    periodic;
-    int          warmupFrames; /* forced refresh just after resuming from background */
+    int          warmupFrames; /* forced refresh just after resuming from background; FIXME: shouldn't be needed */
     /* Preferences: */
     iBool        commandEcho;         /* --echo */
     iBool        forceSoftwareRender; /* --sw */
diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index 9a50b611..0c7ebd54 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -144,8 +144,38 @@ iDefineTypeConstruction(PersistentDocumentState)
 
 /*----------------------------------------------------------------------------------------------*/
 
-static void animateMedia_DocumentWidget_      (iDocumentWidget *d);
-static void updateSideIconBuf_DocumentWidget_   (iDocumentWidget *d);
+iDeclareType(DrawBufs)
+
+enum iDrawBufsFlag {
+    updateSideBuf_DrawBufsFlag      = iBit(1),
+    updateTimestampBuf_DrawBufsFlag = iBit(2),
+};
+
+struct Impl_DrawBufs {
+    int            flags;
+    SDL_Texture *  sideIconBuf;
+    iTextBuf *     timestampBuf;
+};
+
+static void init_DrawBufs(iDrawBufs *d) {
+    d->flags = 0;
+    d->sideIconBuf = NULL;
+    d->timestampBuf = NULL;
+}
+
+static void deinit_DrawBufs(iDrawBufs *d) {
+    delete_TextBuf(d->timestampBuf);
+    if (d->sideIconBuf) {
+        SDL_DestroyTexture(d->sideIconBuf);
+    }
+}
+
+iDefineTypeConstruction(DrawBufs)
+
+/*----------------------------------------------------------------------------------------------*/
+
+static void animateMedia_DocumentWidget_        (iDocumentWidget *d);
+static void updateSideIconBuf_DocumentWidget_   (const iDocumentWidget *d);
 
 static const int smoothDuration_DocumentWidget_  = 600; /* milliseconds */
 static const int outlineMinWidth_DocumentWdiget_ = 45;  /* times gap_UI */
@@ -229,8 +259,7 @@ struct Impl_DocumentWidget {
     iWidget *      playerMenu;
     iVisBuf *      visBuf;
     iPtrSet *      invalidRuns;
-    SDL_Texture *  sideIconBuf;
-    iTextBuf *     timestampBuf;
+    iDrawBufs *    drawBufs; /* dynamic state for drawing */
     iTranslation * translation;
     iWidget *      phoneToolbar;
 };
@@ -291,8 +320,7 @@ void init_DocumentWidget(iDocumentWidget *d) {
     addChild_Widget(w, iClob(d->scroll = new_ScrollWidget()));
     d->menu         = NULL; /* created when clicking */
     d->playerMenu   = NULL;
-    d->sideIconBuf  = NULL;
-    d->timestampBuf = NULL;
+    d->drawBufs     = new_DrawBufs();
     d->translation  = NULL;
     addChildFlags_Widget(w,
                          iClob(new_IndicatorWidget()),
@@ -311,10 +339,7 @@ void init_DocumentWidget(iDocumentWidget *d) {
 
 void deinit_DocumentWidget(iDocumentWidget *d) {
     delete_Translation(d->translation);
-    if (d->sideIconBuf) {
-        SDL_DestroyTexture(d->sideIconBuf);
-    }
-    delete_TextBuf(d->timestampBuf);
+    delete_DrawBufs(d->drawBufs);
     delete_VisBuf(d->visBuf);
     delete_PtrSet(d->invalidRuns);
     iRelease(d->media);
@@ -697,7 +722,7 @@ static void updateVisible_DocumentWidget_(iDocumentWidget *d) {
     }
     const iRangecc newHeading = currentHeading_DocumentWidget_(d);
     if (memcmp(&oldHeading, &newHeading, sizeof(oldHeading))) {
-        updateSideIconBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
     }
     updateHover_DocumentWidget_(d, mouseCoord_Window(get_Window()));
     updateSideOpacity_DocumentWidget_(d, iTrue);
@@ -779,17 +804,21 @@ static void updateWindowTitle_DocumentWidget_(const iDocumentWidget *d) {
     }
 }
 
-static void updateTimestampBuf_DocumentWidget_(iDocumentWidget *d) {
-    if (d->timestampBuf) {
-        delete_TextBuf(d->timestampBuf);
-        d->timestampBuf = NULL;
+static void updateTimestampBuf_DocumentWidget_(const iDocumentWidget *d) {
+    if (!isExposed_Window(get_Window())) {
+        return;
+    }
+    if (d->drawBufs->timestampBuf) {
+        delete_TextBuf(d->drawBufs->timestampBuf);
+        d->drawBufs->timestampBuf = NULL;
     }
     if (isValid_Time(&d->sourceTime)) {
-        d->timestampBuf = new_TextBuf(
+        d->drawBufs->timestampBuf = new_TextBuf(
             uiLabel_FontId,
             white_ColorId,
             cstrCollect_String(format_Time(&d->sourceTime, cstr_Lang("page.timestamp"))));
     }
+    d->drawBufs->flags &= ~updateTimestampBuf_DrawBufsFlag;
 }
 
 static void invalidate_DocumentWidget_(iDocumentWidget *d) {
@@ -819,7 +848,7 @@ void setSource_DocumentWidget(iDocumentWidget *d, const iString *source) {
     documentRunsInvalidated_DocumentWidget_(d);
     updateWindowTitle_DocumentWidget_(d);
     updateVisible_DocumentWidget_(d);
-    updateSideIconBuf_DocumentWidget_(d);
+    d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
     invalidate_DocumentWidget_(d);
     refresh_Widget(as_Widget(d));
 }
@@ -832,7 +861,7 @@ static void updateTheme_DocumentWidget_(iDocumentWidget *d) {
     else {
         setThemeSeed_GmDocument(d->doc, &d->titleUser->chars);
     }
-    updateTimestampBuf_DocumentWidget_(d);
+    d->drawBufs->flags |= updateTimestampBuf_DrawBufsFlag;
 }
 
 static enum iGmDocumentBanner bannerType_DocumentWidget_(const iDocumentWidget *d) {
@@ -928,7 +957,7 @@ static void updateDocument_DocumentWidget_(iDocumentWidget *d, const iGmResponse
         }
         clear_String(&d->sourceMime);
         d->sourceTime = response->when;
-        updateTimestampBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateTimestampBuf_DrawBufsFlag;
         initBlock_String(&str, &response->body);
         if (isSuccess_GmStatusCode(statusCode)) {
             /* Check the MIME type. */
@@ -1075,7 +1104,9 @@ static void cacheRunGlyphs_(void *data, const iGmRun *run) {
 }
 
 static void cacheDocumentGlyphs_DocumentWidget_(const iDocumentWidget *d) {
-    render_GmDocument(d->doc, (iRangei){ 0, size_GmDocument(d->doc).y }, cacheRunGlyphs_, NULL);
+    if (isExposed_Window(get_Window())) {
+        render_GmDocument(d->doc, (iRangei){ 0, size_GmDocument(d->doc).y }, cacheRunGlyphs_, NULL);
+    }
 }
 
 static iBool updateFromHistory_DocumentWidget_(iDocumentWidget *d) {
@@ -1092,14 +1123,14 @@ static iBool updateFromHistory_DocumentWidget_(iDocumentWidget *d) {
         d->sourceTime = resp->when;
         d->sourceStatus = success_GmStatusCode;
         format_String(&d->sourceHeader, cstr_Lang("pageinfo.header.cached"));
-        updateTimestampBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateTimestampBuf_DrawBufsFlag;
         set_Block(&d->sourceContent, &resp->body);
         updateDocument_DocumentWidget_(d, resp, iTrue);
         init_Anim(&d->scrollY, d->initNormScrollY * size_GmDocument(d->doc).y);
         init_Anim(&d->altTextOpacity, 0);
         d->state = ready_RequestState;
         updateSideOpacity_DocumentWidget_(d, iFalse);
-        updateSideIconBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
         updateVisible_DocumentWidget_(d);
         cacheDocumentGlyphs_DocumentWidget_(d);
         postCommandf_App("document.changed doc:%p url:%s", d, cstr_String(d->mod.url));
@@ -1622,7 +1653,7 @@ static iBool handleCommand_DocumentWidget_(iDocumentWidget *d, const char *cmd)
         d->phoneToolbar = findWidget_App("toolbar");
         const iBool keepCenter = equal_Command(cmd, "font.changed");
         updateDocumentWidthRetainingScrollPosition_DocumentWidget_(d, keepCenter);
-        updateSideIconBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
         invalidate_DocumentWidget_(d);
         dealloc_VisBuf(d->visBuf);
         updateWindowTitle_DocumentWidget_(d);
@@ -1643,7 +1674,7 @@ static iBool handleCommand_DocumentWidget_(iDocumentWidget *d, const char *cmd)
         updateTheme_DocumentWidget_(d);
         updateVisible_DocumentWidget_(d);
         updateTrust_DocumentWidget_(d, NULL);
-        updateSideIconBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
         invalidate_DocumentWidget_(d);
         refresh_Widget(w);
     }
@@ -1875,7 +1906,7 @@ static iBool handleCommand_DocumentWidget_(iDocumentWidget *d, const char *cmd)
         }
         iReleasePtr(&d->request);
         updateVisible_DocumentWidget_(d);
-        updateSideIconBuf_DocumentWidget_(d);
+        d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
         postCommandf_App("document.changed doc:%p url:%s", d, cstr_String(d->mod.url));
         /* Check for a pending goto. */
         if (!isEmpty_String(&d->pendingGotoHeading)) {
@@ -3258,10 +3289,15 @@ static iBool isSideHeadingVisible_DocumentWidget_(const iDocumentWidget *d) {
     return sideElementAvailWidth_DocumentWidget_(d) >= lineHeight_Text(banner_FontId) * 4.5f;
 }
 
-static void updateSideIconBuf_DocumentWidget_(iDocumentWidget *d) {
-    if (d->sideIconBuf) {
-        SDL_DestroyTexture(d->sideIconBuf);
-        d->sideIconBuf = NULL;
+static void updateSideIconBuf_DocumentWidget_(const iDocumentWidget *d) {
+    if (!isExposed_Window(get_Window())) {
+        return;
+    }
+    iDrawBufs *dbuf = d->drawBufs;
+    dbuf->flags &= ~updateSideBuf_DrawBufsFlag;
+    if (dbuf->sideIconBuf) {
+        SDL_DestroyTexture(dbuf->sideIconBuf);
+        dbuf->sideIconBuf = NULL;
     }
     const iGmRun *banner = siteBanner_GmDocument(d->doc);
     if (!banner) {
@@ -3286,13 +3322,13 @@ static void updateSideIconBuf_DocumentWidget_(iDocumentWidget *d) {
         }
     }
     SDL_Renderer *render = renderer_Window(get_Window());
-    d->sideIconBuf = SDL_CreateTexture(render,
-                                       SDL_PIXELFORMAT_RGBA4444,
-                                       SDL_TEXTUREACCESS_STATIC | SDL_TEXTUREACCESS_TARGET,
-                                       bufSize.x, bufSize.y);
+    dbuf->sideIconBuf = SDL_CreateTexture(render,
+                                          SDL_PIXELFORMAT_RGBA4444,
+                                          SDL_TEXTUREACCESS_STATIC | SDL_TEXTUREACCESS_TARGET,
+                                          bufSize.x, bufSize.y);
     iPaint p;
     init_Paint(&p);
-    beginTarget_Paint(&p, d->sideIconBuf);
+    beginTarget_Paint(&p, dbuf->sideIconBuf);
     const iColor back = get_Color(tmBannerSideTitle_ColorId);
     SDL_SetRenderDrawColor(render, back.r, back.g, back.b, 0); /* better blending of the edge */
     SDL_RenderClear(render);
@@ -3309,7 +3345,7 @@ static void updateSideIconBuf_DocumentWidget_(iDocumentWidget *d) {
         drawWrapRange_Text(font, pos, avail, tmBannerSideTitle_ColorId, text);
     }
     endTarget_Paint(&p);
-    SDL_SetTextureBlendMode(d->sideIconBuf, SDL_BLENDMODE_BLEND);
+    SDL_SetTextureBlendMode(dbuf->sideIconBuf, SDL_BLENDMODE_BLEND);
 }
 
 static void drawSideElements_DocumentWidget_(const iDocumentWidget *d) {
@@ -3319,12 +3355,13 @@ static void drawSideElements_DocumentWidget_(const iDocumentWidget *d) {
     const int      margin    = gap_UI * d->pageMargin;
     float          opacity   = value_Anim(&d->sideOpacity);
     const int      avail     = left_Rect(docBounds) - left_Rect(bounds) - 2 * margin;
-    iPaint      p;
+    iDrawBufs *    dbuf      = d->drawBufs;
+    iPaint         p;
     init_Paint(&p);
     setClip_Paint(&p, bounds);
     /* Side icon and current heading. */
-    if (prefs_App()->sideIcon && opacity > 0 && d->sideIconBuf) {
-        const iInt2 texSize = size_SDLTexture(d->sideIconBuf);
+    if (prefs_App()->sideIcon && opacity > 0 && dbuf->sideIconBuf) {
+        const iInt2 texSize = size_SDLTexture(dbuf->sideIconBuf);
         if (avail > texSize.x) {
             const int minBannerSize = lineHeight_Text(banner_FontId) * 2;
             iInt2 pos = addY_I2(add_I2(topLeft_Rect(bounds), init_I2(margin, 0)),
@@ -3332,20 +3369,20 @@ static void drawSideElements_DocumentWidget_(const iDocumentWidget *d) {
                                     (texSize.y > minBannerSize
                                          ? (gap_Text + lineHeight_Text(heading3_FontId)) / 2
                                          : 0));
-            SDL_SetTextureAlphaMod(d->sideIconBuf, 255 * opacity);
+            SDL_SetTextureAlphaMod(dbuf->sideIconBuf, 255 * opacity);
             SDL_RenderCopy(renderer_Window(get_Window()),
-                           d->sideIconBuf, NULL,
+                           dbuf->sideIconBuf, NULL,
                            &(SDL_Rect){ pos.x, pos.y, texSize.x, texSize.y });
         }
     }
     /* Reception timestamp. */
-    if (d->timestampBuf && d->timestampBuf->size.x <= avail) {
+    if (dbuf->timestampBuf && dbuf->timestampBuf->size.x <= avail) {
         draw_TextBuf(
-            d->timestampBuf,
+            dbuf->timestampBuf,
             add_I2(
                 bottomLeft_Rect(bounds),
                 init_I2(margin,
-                        -margin + -d->timestampBuf->size.y +
+                        -margin + -dbuf->timestampBuf->size.y +
                             iMax(0, scrollMax_DocumentWidget_(d) - value_Anim(&d->scrollY)))),
             tmQuoteIcon_ColorId);
     }
@@ -3378,6 +3415,12 @@ static void draw_DocumentWidget_(const iDocumentWidget *d) {
         return;
     }
     draw_Widget(w);
+    if (d->drawBufs->flags & updateTimestampBuf_DrawBufsFlag) {
+        updateTimestampBuf_DocumentWidget_(d);
+    }
+    if (d->drawBufs->flags & updateSideBuf_DrawBufsFlag) {
+        updateSideIconBuf_DocumentWidget_(d);
+    }
     allocVisBuffer_DocumentWidget_(d);
     const iRect ctxWidgetBounds = init_Rect(
         0, 0, width_Rect(bounds) - constAs_Widget(d->scroll)->rect.size.x, height_Rect(bounds));
@@ -3617,7 +3660,7 @@ iBool isRequestOngoing_DocumentWidget(const iDocumentWidget *d) {
 void updateSize_DocumentWidget(iDocumentWidget *d) {
     updateDocumentWidthRetainingScrollPosition_DocumentWidget_(d, iFalse);
     resetWideRuns_DocumentWidget_(d);
-    updateSideIconBuf_DocumentWidget_(d);
+    d->drawBufs->flags |= updateSideBuf_DrawBufsFlag;
     updateVisible_DocumentWidget_(d);
     invalidate_DocumentWidget_(d);
 }
diff --git a/src/ui/text.c b/src/ui/text.c
index 674e2a72..6af7d6d1 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -24,6 +24,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
 #include "color.h"
 #include "metrics.h"
 #include "embedded.h"
+#include "window.h"
 #include "app.h"
 
 #define STB_TRUETYPE_IMPLEMENTATION
@@ -702,6 +703,7 @@ void cacheTextGlyphs_Font_(iFont *d, const iRangecc text) {
     iArray *     rasters = NULL;
     SDL_Texture *oldTarget = NULL;
     iBool        isTargetChanged = iFalse;
+    iAssert(isExposed_Window(get_Window()));
     /* We'll flush the buffered rasters periodically until everything is cached. */
     while (chPos < text.end) {
         while (chPos < text.end) {
@@ -1017,7 +1019,7 @@ static iRect run_Font_(iFont *d, const iRunArgs *args) {
         int x1 = iMax(xpos, xposExtend);
         /* Which half of the pixel the glyph falls on? */
         const int hoff = enableHalfPixelGlyphs_Text ? (xpos - x1 > 0.5f ? 1 : 0) : 0;
-        if (!isRasterized_Glyph_(glyph, hoff)) {
+        if (mode & draw_RunMode && !isRasterized_Glyph_(glyph, hoff)) {
             /* Need to pause here and make sure all glyphs have been cached in the text. */
             cacheTextGlyphs_Font_(d, args->text);
             glyph = glyph_Font_(d, ch); /* cache may have been reset */
diff --git a/src/ui/window.c b/src/ui/window.c
index f92107e3..27740326 100644
--- a/src/ui/window.c
+++ b/src/ui/window.c
@@ -1769,12 +1769,8 @@ iBool processEvent_Window(iWindow *d, const SDL_Event *ev) {
             SDL_Event event = *ev;
             if (event.type == SDL_USEREVENT && isCommand_UserEvent(ev, "window.unfreeze")) {
                 d->isDrawFrozen = iFalse;
-                /* When the window is shown for the first time, ensure glyphs get
-                   re-cached correctly. */
                 if (SDL_GetWindowFlags(d->win) & SDL_WINDOW_HIDDEN) {
                     SDL_ShowWindow(d->win);
-                    resetFonts_Text();
-                    postCommand_App("theme.changed");
                 }
                 postRefresh_App();
                 return iTrue;
diff --git a/src/ui/window.h b/src/ui/window.h
index 7303acb2..6960e03e 100644
--- a/src/ui/window.h
+++ b/src/ui/window.h
@@ -113,3 +113,8 @@ iWindow *   get_Window              (void);
 #if defined (LAGRANGE_CUSTOM_FRAME)
 SDL_HitTestResult hitTest_Window(const iWindow *d, iInt2 pos);
 #endif
+
+iLocalDef iBool isExposed_Window(const iWindow *d) {
+    iAssert(d);
+    return d->isExposed;
+}