Attachment 122986 Details for Bug 94962 – The code reproducing the error.

The code reproducing the error.

CairoBug.c (text/plain), 2.08 KB, created by Zoltan Turanyi on 2016-04-16 09:25:25 UTC

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Creator: Zoltan Turanyi

Created: 2016-04-16 09:25:25 UTC

Size: 2.08 KB

patch

obsolete

>#include "stdio.h"
>#include "cairo.h"
>
>cairo_status_t write_func(void * closure, const unsigned char *data, unsigned length)
>{
>    if (closure==NULL) return CAIRO_STATUS_SUCCESS;
>    if (length == fwrite(data, 1, length, (FILE*)closure))
>        return CAIRO_STATUS_SUCCESS;
>    else
>        return CAIRO_STATUS_WRITE_ERROR;
>}
>
>int main()
>{
>    /* Vary these input parameters */
>    const int offset = 20000; /* How much do we offset our elements in Y direction. */
>    const double scale = 1.6; /* How much scaling do we want to apply */
>
>    /* Additional preparation */
>    const int viewport_x = 200, viewport_y= 200; /* The size of our viewport in pixels.*/
>    char scale_text[1000];
>    char fname[1000];
>    sprintf(scale_text, "scale: %g, offset: %i", scale, offset);
>    sprintf(fname, "test_%i_%i.png", (int)(scale*100), offset);
>
>    /* Record a simple line and text at y position of 'offset'. */
>    /* Note that the recorded surface does not depend on scale or
>     * offset other than the text output */
>    cairo_surface_t *rec = cairo_recording_surface_create(CAIRO_CONTENT_COLOR_ALPHA, NULL);
>    cairo_t *cr = cairo_create(rec);
>    cairo_move_to(cr, 0, offset);
>    cairo_line_to(cr, 100, offset);
>    cairo_stroke(cr);
>    cairo_move_to(cr, 0, offset);
>    cairo_show_text(cr, scale_text);
>    cairo_destroy(cr);
>
>
>    /* Replay the recorded surface to an image scaled by 'scale'.
>    * (We only play back a small area of it around our elements to reduce
>    * output image size to 'viewport'.)*/
>    cairo_surface_t *surf = cairo_image_surface_create(CAIRO_FORMAT_RGB24, viewport_x, viewport_y);
>    cr = cairo_create(surf);
>    cairo_set_source_rgb(cr, 1, 1, 1);
>    cairo_rectangle(cr, 0, 0, viewport_x, viewport_y);
>    cairo_fill(cr);
>    cairo_scale(cr, scale, scale);
>    cairo_set_source_surface(cr, rec, 0, -offset+viewport_y/2/scale);
>    cairo_paint(cr);
>    cairo_destroy(cr);
>    FILE *outFile = fopen(fname, "wb");
>    cairo_surface_write_to_png_stream(surf, write_func, outFile);
>    fclose(outFile);
>    cairo_surface_destroy(surf);
>}

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Attachments on bug 94962: 122986 | 122987 | 122988 | 122989 | 122990

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