* Add support for integral symbols in Cairo renderer

1 files changed, 136 insertions, 0 deletions

diff --git a/cairo/gmathcairo_renderers.c b/cairo/gmathcairo_renderers.c
index a4da1ae..9c262f6 100644
--- a/cairo/gmathcairo_renderers.c
+++ b/cairo/gmathcairo_renderers.c
@@ -1003,6 +1003,141 @@ render_product (GMathCairoContext *ccontext, GMathSymbol *symbol, float size)
     return boxed;
 }
 
+/* Render an integral symbol */
+GMathBoxed*
+render_integral (GMathCairoContext *ccontext, GMathSymbol *symbol, float size)
+{
+    GMathBoxed      *boxed;
+    cairo_surface_t *surface;
+    GMathBoxed      **children;
+    cairo_surface_t *main_surf;
+    cairo_t         *cr;
+    int             width, height, width0, height0, width1;
+    int             dwr, dhr, dwt, dht, dwb, dhb;
+    int             x, y, x0, y0;
+    float           size_small = size * 0.5;
+
+    if (!symbol || !symbol->children[2])
+        return NULL;
+
+    children = g_new0 (GMathBoxed*, 3);
+
+    dwr = dwt = dwb = 0;
+    dhr = dht = dhb = 0;
+
+    children[2] = gmathcairo_render_symbol (ccontext, symbol->children[2],
+                                            size);
+    if (!children[2])
+    {
+        g_free (children);
+        return NULL;
+    }
+    width = dwr = children[2]->box.width;
+    height = dhr = children[2]->box.height;
+
+    height0 = height;
+    width0 = height0 * 0.6;
+    main_surf = draw_integral (width0, height0);
+
+    width += width0;
+    width1 = width0;
+
+    if (symbol->children[1])
+    {
+        children[1] = gmathcairo_render_symbol (ccontext, symbol->children[1],
+                                                size_small);
+        if (ccontext->editor_mode && !children[1])
+            children[1] = gmathcairo_render_empty (ccontext,
+                                                   symbol->children[1],
+                                                   size_small);
+        if (children[1])
+        {
+            dwt = children[1]->box.width;
+            dht = children[1]->box.height;
+            width += dwt;
+            width1 += dwt;
+        }
+    }
+    if (symbol->children[0])
+    {
+        children[0] = gmathcairo_render_symbol (ccontext, symbol->children[0],
+                                                size_small);
+        if (ccontext->editor_mode && !children[0])
+            children[0] = gmathcairo_render_empty (ccontext,
+                                                   symbol->children[0],
+                                                   size_small);
+        if (children[0])
+        {
+            dwb = children[0]->box.width;
+            dhb = children[0]->box.height;
+            if (dwb > dwt + 0.6 * width0)
+            {
+                width += dwb - dwt - 0.6 * width0;
+                width1 += dwb - dwt - 0.6 * width0;
+            }
+        }
+    }
+
+    x0 = 0;
+    y0 = 0;
+
+    boxed = gmathboxed_new (symbol);
+    gmathboxed_resize (boxed, width, height);
+
+    surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, width, height);
+    boxed->surface = surface;
+    cr = cairo_create (surface);
+    cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
+
+    cairo_save (cr);
+    cairo_set_source_surface (cr, main_surf, x0, y0);
+    cairo_paint (cr);
+    cairo_restore (cr);
+    cairo_surface_destroy (main_surf);
+
+    if (children[2])
+    {
+        x = width1;
+        y = y0 + (height - dhr) / 2;
+        gmathboxed_add_child (boxed, children[2], x, y);
+        cairo_save (cr);
+        cairo_set_source_surface (cr, children[2]->surface, x, y);
+        cairo_paint (cr);
+        cairo_restore (cr);
+        gmathboxed_destroy_surface (children[2]);
+    }
+
+    if (children[1])
+    {
+        x = x0 + width0;
+        y = 0;
+        gmathboxed_add_child (boxed, children[1], x, y);
+        cairo_save (cr);
+        cairo_set_source_surface (cr, children[1]->surface, x, y);
+        cairo_paint (cr);
+        cairo_restore (cr);
+        gmathboxed_destroy_surface (children[1]);
+    }
+
+    if (children[0])
+    {
+        x = x0 + width0 * 0.6;
+        y = height - dhb;
+        gmathboxed_add_child (boxed, children[0], x, y);
+        cairo_save (cr);
+        cairo_set_source_surface (cr, children[0]->surface, x, y);
+        cairo_paint (cr);
+        cairo_restore (cr);
+        gmathboxed_destroy_surface (children[0]);
+    }
+
+    /* Free things */
+    cairo_destroy (cr);
+    g_free (children);
+
+    return boxed;
+}
+
 /* Register renderers */
 void
 gmathcairo_register_renderers (GMathCairoContext *ccontext)
@@ -1026,6 +1161,7 @@ gmathcairo_register_renderers (GMathCairoContext *ccontext)
     gmathcairocontext_register_renderer (ccontext, "super", render_super);
     gmathcairocontext_register_renderer (ccontext, "sum", render_sum);
     gmathcairocontext_register_renderer (ccontext, "product", render_product);
+    gmathcairocontext_register_renderer (ccontext, "integral", render_integral);
 
     /* Special chars */
     gmathcairocontext_register_renderer (ccontext, "alpha", render_char);