dwrite: Implement paragraph alignment.

dlls/dwrite/layout.c

@@ -342,6 +342,16 @@ static inline HRESULT format_set_textalignment(struct dwrite_textformat_data *fo
     return S_OK;
 }
 
+static inline HRESULT format_set_paralignment(struct dwrite_textformat_data *format,
+    DWRITE_PARAGRAPH_ALIGNMENT alignment, BOOL *changed)
+{
+    if ((UINT32)alignment > DWRITE_PARAGRAPH_ALIGNMENT_CENTER)
+        return E_INVALIDARG;
+    if (changed) *changed = format->paralign != alignment;
+    format->paralign = alignment;
+    return S_OK;
+}
+
 static HRESULT get_fontfallback_from_format(const struct dwrite_textformat_data *format, IDWriteFontFallback **fallback)
 {
     *fallback = format->fallback;
@@ -1182,6 +1192,50 @@ static void layout_apply_text_alignment(struct dwrite_textlayout *layout)
     }
 }
 
+static void layout_apply_par_alignment(struct dwrite_textlayout *layout)
+{
+    struct layout_effective_inline *inrun;
+    struct layout_effective_run *erun;
+    FLOAT origin_y = 0.0;
+    UINT32 line;
+
+    /* alignment mode defines origin, after that all run origins are updated
+       the same way */
+
+    switch (layout->format.paralign)
+    {
+    case DWRITE_PARAGRAPH_ALIGNMENT_NEAR:
+        origin_y = 0.0;
+        break;
+    case DWRITE_PARAGRAPH_ALIGNMENT_FAR:
+        origin_y = layout->metrics.layoutHeight - layout->metrics.height;
+        break;
+    case DWRITE_PARAGRAPH_ALIGNMENT_CENTER:
+        origin_y = (layout->metrics.layoutHeight - layout->metrics.height) / 2.0;
+        break;
+    default:
+        ;
+    }
+
+    layout->metrics.top = origin_y;
+
+    erun = layout_get_next_erun(layout, NULL);
+    inrun = layout_get_next_inline_run(layout, NULL);
+    for (line = 0; line < layout->metrics.lineCount; line++) {
+        origin_y += layout->lines[line].baseline;
+
+        while (erun && erun->line == line) {
+            erun->origin_y = origin_y;
+            erun = layout_get_next_erun(layout, erun);
+        }
+
+        while (inrun && inrun->line == line) {
+            inrun->origin_y = origin_y;
+            inrun = layout_get_next_inline_run(layout, inrun);
+        }
+    }
+}
+
 static HRESULT layout_compute_effective_runs(struct dwrite_textlayout *layout)
 {
     struct layout_effective_inline *inrun;
@@ -1354,6 +1408,10 @@ static HRESULT layout_compute_effective_runs(struct dwrite_textlayout *layout)
     if (layout->format.textalignment != DWRITE_TEXT_ALIGNMENT_LEADING)
         layout_apply_text_alignment(layout);
 
+    /* initial paragraph alignment is always near */
+    if (layout->format.paralign != DWRITE_PARAGRAPH_ALIGNMENT_NEAR)
+        layout_apply_par_alignment(layout);
+
     layout->metrics.heightIncludingTrailingWhitespace = layout->metrics.height; /* FIXME: not true for vertical text */
 
     layout->recompute &= ~RECOMPUTE_EFFECTIVE_RUNS;
@@ -2072,7 +2130,6 @@ static HRESULT WINAPI dwritetextlayout_SetTextAlignment(IDWriteTextLayout2 *ifac
 static HRESULT WINAPI dwritetextlayout_SetParagraphAlignment(IDWriteTextLayout2 *iface, DWRITE_PARAGRAPH_ALIGNMENT alignment)
 {
     struct dwrite_textlayout *This = impl_from_IDWriteTextLayout2(iface);
-    TRACE("(%p)->(%d)\n", This, alignment);
     return IDWriteTextFormat1_SetParagraphAlignment(&This->IDWriteTextFormat1_iface, alignment);
 }
 
@@ -3100,8 +3157,20 @@ static HRESULT WINAPI dwritetextformat1_layout_SetTextAlignment(IDWriteTextForma
 static HRESULT WINAPI dwritetextformat1_layout_SetParagraphAlignment(IDWriteTextFormat1 *iface, DWRITE_PARAGRAPH_ALIGNMENT alignment)
 {
     struct dwrite_textlayout *This = impl_layout_form_IDWriteTextFormat1(iface);
-    FIXME("(%p)->(%d): stub\n", This, alignment);
-    return E_NOTIMPL;
+    BOOL changed;
+    HRESULT hr;
+
+    TRACE("(%p)->(%d)\n", This, alignment);
+
+    hr = format_set_paralignment(&This->format, alignment, &changed);
+    if (FAILED(hr))
+        return hr;
+
+    /* if layout is not ready there's nothing to align */
+    if (changed && !(This->recompute & RECOMPUTE_EFFECTIVE_RUNS))
+        layout_apply_par_alignment(This);
+
+    return S_OK;
 }
 
 static HRESULT WINAPI dwritetextformat1_layout_SetWordWrapping(IDWriteTextFormat1 *iface, DWRITE_WORD_WRAPPING wrapping)
@@ -3974,14 +4043,8 @@ static HRESULT WINAPI dwritetextformat_SetTextAlignment(IDWriteTextFormat1 *ifac
 static HRESULT WINAPI dwritetextformat_SetParagraphAlignment(IDWriteTextFormat1 *iface, DWRITE_PARAGRAPH_ALIGNMENT alignment)
 {
     struct dwrite_textformat *This = impl_from_IDWriteTextFormat1(iface);
-
     TRACE("(%p)->(%d)\n", This, alignment);
-
-    if ((UINT32)alignment > DWRITE_PARAGRAPH_ALIGNMENT_CENTER)
-        return E_INVALIDARG;
-
-    This->format.paralign = alignment;
-    return S_OK;
+    return format_set_paralignment(&This->format, alignment, NULL);
 }
 
 static HRESULT WINAPI dwritetextformat_SetWordWrapping(IDWriteTextFormat1 *iface, DWRITE_WORD_WRAPPING wrapping)

dlls/dwrite/tests/layout.c

@@ -2972,6 +2972,100 @@ static void test_SetTextAlignment(void)
     IDWriteFactory_Release(factory);
 }
 
+static void test_SetParagraphAlignment(void)
+{
+    static const WCHAR strW[] = {'a',0};
+    DWRITE_TEXT_METRICS metrics;
+    IDWriteTextFormat *format;
+    IDWriteTextLayout *layout;
+    IDWriteFactory *factory;
+    DWRITE_PARAGRAPH_ALIGNMENT v;
+    DWRITE_LINE_METRICS lines[1];
+    UINT32 count;
+    HRESULT hr;
+
+    factory = create_factory();
+
+    hr = IDWriteFactory_CreateTextFormat(factory, tahomaW, NULL, DWRITE_FONT_WEIGHT_NORMAL, DWRITE_FONT_STYLE_NORMAL,
+        DWRITE_FONT_STRETCH_NORMAL, 12.0, enusW, &format);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    v = IDWriteTextFormat_GetParagraphAlignment(format);
+    ok(v == DWRITE_PARAGRAPH_ALIGNMENT_NEAR, "got %d\n", v);
+
+    hr = IDWriteFactory_CreateTextLayout(factory, strW, 1, format, 500.0, 100.0, &layout);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    v = IDWriteTextLayout_GetParagraphAlignment(layout);
+    ok(v == DWRITE_PARAGRAPH_ALIGNMENT_NEAR, "got %d\n", v);
+
+    hr = IDWriteTextLayout_SetParagraphAlignment(layout, DWRITE_PARAGRAPH_ALIGNMENT_FAR);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    hr = IDWriteTextLayout_SetParagraphAlignment(layout, DWRITE_PARAGRAPH_ALIGNMENT_FAR);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    v = IDWriteTextFormat_GetParagraphAlignment(format);
+    ok(v == DWRITE_PARAGRAPH_ALIGNMENT_NEAR, "got %d\n", v);
+
+    v = IDWriteTextLayout_GetParagraphAlignment(layout);
+    ok(v == DWRITE_PARAGRAPH_ALIGNMENT_FAR, "got %d\n", v);
+
+    hr = IDWriteTextLayout_SetParagraphAlignment(layout, DWRITE_PARAGRAPH_ALIGNMENT_CENTER);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    v = IDWriteTextLayout_GetParagraphAlignment(layout);
+    ok(v == DWRITE_PARAGRAPH_ALIGNMENT_CENTER, "got %d\n", v);
+
+    count = 0;
+    hr = IDWriteTextLayout_GetLineMetrics(layout, lines, 1, &count);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+    ok(count == 1, "got %u\n", count);
+
+    /* maxheight is 100, near alignment */
+    hr = IDWriteTextLayout_SetParagraphAlignment(layout, DWRITE_PARAGRAPH_ALIGNMENT_NEAR);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    hr = IDWriteTextLayout_GetMetrics(layout, &metrics);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    ok(metrics.top == 0.0, "got %.2f\n", metrics.top);
+    ok(metrics.height == lines[0].height, "got %.2f\n", metrics.height);
+    ok(metrics.layoutHeight == 100.0, "got %.2f\n", metrics.layoutHeight);
+    ok(metrics.lineCount == 1, "got %d\n", metrics.lineCount);
+
+    /* maxwidth is 100, far alignment */
+    hr = IDWriteTextLayout_SetParagraphAlignment(layout, DWRITE_PARAGRAPH_ALIGNMENT_FAR);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    hr = IDWriteTextLayout_GetMetrics(layout, &metrics);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    ok(metrics.top == metrics.layoutHeight - metrics.height, "got %.2f\n", metrics.top);
+    ok(metrics.height == lines[0].height, "got %.2f\n", metrics.height);
+    ok(metrics.layoutHeight == 100.0, "got %.2f\n", metrics.layoutHeight);
+    ok(metrics.lineCount == 1, "got %d\n", metrics.lineCount);
+    IDWriteTextLayout_Release(layout);
+
+    /* initially created with centered alignment */
+    hr = IDWriteTextFormat_SetParagraphAlignment(format, DWRITE_PARAGRAPH_ALIGNMENT_CENTER);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    hr = IDWriteFactory_CreateTextLayout(factory, strW, 1, format, 500.0, 100.0, &layout);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    hr = IDWriteTextLayout_GetMetrics(layout, &metrics);
+    ok(hr == S_OK, "got 0x%08x\n", hr);
+
+    ok(metrics.top == (metrics.layoutHeight - lines[0].height) / 2, "got %.2f\n", metrics.top);
+    ok(metrics.height == lines[0].height, "got %.2f\n", metrics.height);
+    ok(metrics.lineCount == 1, "got %d\n", metrics.lineCount);
+    IDWriteTextLayout_Release(layout);
+
+    IDWriteTextFormat_Release(format);
+    IDWriteFactory_Release(factory);
+}
+
 START_TEST(layout)
 {
     static const WCHAR ctrlstrW[] = {0x202a,0};
@@ -3013,6 +3107,7 @@ START_TEST(layout)
     test_SetDrawingEffect();
     test_GetLineMetrics();
     test_SetTextAlignment();
+    test_SetParagraphAlignment();
 
     IDWriteFactory_Release(factory);
 }