Attachment 18451 Details for Bug 17242 – testing sample code

testing sample code

cairo_mask.cpp (text/x-c++src), 1.33 KB, created by david_wu on 2008-08-21 06:43:03 UTC

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Creator: david_wu

Created: 2008-08-21 06:43:03 UTC

Size: 1.33 KB

patch

obsolete

>#include <stdio.h>
>#include <cairo/cairo.h>
>
>void printdata(const char* msg, unsigned char* data, int stride)
>{
>	printf("%s\n", msg);
>	unsigned char* line = data;
>	for (int i = 0; i < 1; i++)
>	{
>		for (int j = 0; j < stride; j++)
>		{
>			printf("%02X", line[j]);
>		}
>		line += stride;
>		printf("\n");
>	}
>	printf("\n");
>}
>
>int main(void)
>{
>	unsigned char sourceWhite[] = { 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff };
>	unsigned char maskA8[] = { 0x00,0xff,0x00,0x00 };
>
>	cairo_surface_t* target = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, 2, 1);
>	cairo_surface_t* source = cairo_image_surface_create_for_data(sourceWhite, CAIRO_FORMAT_ARGB32, 2, 1, 8);
>	cairo_surface_t* mask = cairo_image_surface_create_for_data(maskA8, CAIRO_FORMAT_A8, 2, 1, 4);
>
>	unsigned char* data = cairo_image_surface_get_data(target);
>	int stride = cairo_image_surface_get_stride(target);
>	cairo_t* cr = cairo_create(target);
>
>	double alpha = 0.5;
>
>
>	printdata("initial:\n", data, stride);
>
>	cairo_set_source_surface(cr, source, 0, 0);
>	cairo_paint_with_alpha(cr, alpha);
>
>	printdata("paint with alpha:\n", data, stride);
>
>	cairo_set_source_rgba(cr, 1.0, 1.0, 1.0, alpha);
>	cairo_mask_surface(cr, mask, 0, 0);
>
>	printdata("mask rgba:\n", data, stride);
>
>
>	cairo_surface_destroy(target);
>	cairo_surface_destroy(source);
>	cairo_surface_destroy(mask);
>
>	cairo_destroy(cr);
>	return 0;
>}

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Attachments on bug 17242: 18451

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