lib/igt_fb: api documentation

Also realign function parameters and replace abort() with igt_fail()
while at it.

v2: Forgotten to add a nice intro.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2014-03-26 16:37:15 +01:00
parent 7568edf4b1
commit 3d9e63f2ad
2 changed files with 217 additions and 18 deletions

View File

@ -38,6 +38,17 @@
* @short_description: Framebuffer handling and drawing library
* @title: i-g-t framebuffer
* @include: igt_fb.h
*
* This library contains helper functions for handling kms framebuffer objects
* using #igt_fb structures to track all the metadata. igt_create_fb() creates
* a basic framebufffer and igt_remove_fb() cleans everything up again.
*
* It also supports drawing using the cairo library and provides some simplified
* helper functions to easily draw test patterns. The main function to create a
* cairo drawing context for a framebuffer object is igt_get_cairo_ctx().
*
* Finally it also pulls in the drm fourcc headers and provides some helper
* functions to work with these pixel format codes.
*/
/* drm fourcc/cairo format maps */
@ -107,25 +118,68 @@ static int create_bo_for_fb(int fd, int width, int height, int bpp,
return 0;
}
/**
* igt_paint_color:
* @cr: cairo drawing context
* @x: pixel x-coordination of the fill rectangle
* @y: pixel y-coordination of the fill rectangle
* @w: width of the fill rectangle
* @h: height of the fill rectangle
* @r: red value to use as fill color
* @g: gree value to use as fill color
* @b: blue value to use as fill color
*
* This functions draws a solid rectangle with the given color using the drawing
* context @cr.
*/
void igt_paint_color(cairo_t *cr, int x, int y, int w, int h,
double r, double g, double b)
double r, double g, double b)
{
cairo_rectangle(cr, x, y, w, h);
cairo_set_source_rgb(cr, r, g, b);
cairo_fill(cr);
}
/**
* igt_paint_color_alpha:
* @cr: cairo drawing context
* @x: pixel x-coordination of the fill rectangle
* @y: pixel y-coordination of the fill rectangle
* @w: width of the fill rectangle
* @h: height of the fill rectangle
* @r: red value to use as fill color
* @g: gree value to use as fill color
* @b: blue value to use as fill color
* @a: alpha value to use as fill color
*
* This functions draws a rectangle with the given color and alpha values using
* the drawing context @cr.
*/
void igt_paint_color_alpha(cairo_t *cr, int x, int y, int w, int h,
double r, double g, double b, double a)
double r, double g, double b, double a)
{
cairo_rectangle(cr, x, y, w, h);
cairo_set_source_rgba(cr, r, g, b, a);
cairo_fill(cr);
}
/**
* igt_paint_color_gradient:
* @cr: cairo drawing context
* @x: pixel x-coordination of the fill rectangle
* @y: pixel y-coordination of the fill rectangle
* @w: width of the fill rectangle
* @h: height of the fill rectangle
* @r: red value to use as fill color
* @g: gree value to use as fill color
* @b: blue value to use as fill color
*
* This functions draws a gradient into the rectangle which fades in from black
* to the given values using the drawing context @cr.
*/
void
igt_paint_color_gradient(cairo_t *cr, int x, int y, int w, int h,
int r, int g, int b)
int r, int g, int b)
{
cairo_pattern_t *pat;
@ -162,6 +216,21 @@ paint_test_patterns(cairo_t *cr, int width, int height)
igt_paint_color_gradient(cr, x, y, gr_width, gr_height, 1, 1, 1);
}
/**
* igt_cairo_printf_line:
* @cr: cairo drawing context
* @align: text alignment
* @yspacing: additional y-direction feed after this line
* @fmt: format string
* @...: optional arguments used in the format string
*
* This is a little helper to draw text onto framebuffers. All the initial setup
* (like setting the font size and the moving to the starting position) still
* needs to be done manually with explicit cairo calls on @cr.
*
* Returns:
* The width of the drawn text.
*/
int igt_cairo_printf_line(cairo_t *cr, enum igt_text_align align,
double yspacing, const char *fmt, ...)
{
@ -236,6 +305,20 @@ paint_marker(cairo_t *cr, int x, int y)
igt_cairo_printf_line(cr, align, 0, "(%d, %d)", x, y);
}
/**
* igt_paint_test_pattern:
* @cr: cairo drawing context
* @width: width of the visible area
* @height: height of the visible area
*
* This functions draws an entire set of test patterns for the given visible
* area using the drawing context @cr. This is useful for manual visual
* inspection of displayed framebuffers.
*
* The test patterns include
* - corner markers to check for over/underscan and
* - a set of color and b/w gradients.
*/
void igt_paint_test_pattern(cairo_t *cr, int width, int height)
{
paint_test_patterns(cr, width, height);
@ -251,8 +334,21 @@ void igt_paint_test_pattern(cairo_t *cr, int width, int height)
igt_assert(!cairo_status(cr));
}
/**
* igt_paint_image:
* @cr: cairo drawing context
* @filename: filename of the png image to draw
* @dst_x: pixel x-coordination of the destination rectangle
* @dst_y: pixel y-coordination of the destination rectangle
* @dst_width: width of the destination rectangle
* @dst_height: height of the destination rectangle
*
* This function can be used to draw a scaled version of the supplied png image.
* This is currently only used by the CR-code based testing in the "testdisplay"
* testcase.
*/
void igt_paint_image(cairo_t *cr, const char *filename,
int dst_x, int dst_y, int dst_width, int dst_height)
int dst_x, int dst_y, int dst_width, int dst_height)
{
cairo_surface_t *image;
int img_width, img_height;
@ -279,8 +375,28 @@ void igt_paint_image(cairo_t *cr, const char *filename,
cairo_restore(cr);
}
/**
* igt_create_fb:
* @fd: open i915 drm file descriptor
* @width: width of the framebuffer in pixel
* @height: height of the framebuffer in pixel
* @format: drm fourcc pixel format code
* @tiled: X-tiled or linear framebuffer
* @fb: pointer to an #igt_fb structure
*
* This function allocates a gem buffer object suitable to back a framebuffer
* with the requested properties and then wraps it up in a drm framebuffer
* object. All metadata is stored in @fb.
*
* The backing storage of the framebuffer is filled with all zeros, i.e. black
* for rgb pixel formats.
*
* Returns:
* The kms id of the created framebuffer on success or a negative error code on
* failure.
*/
unsigned int igt_create_fb(int fd, int width, int height, uint32_t format,
bool tiled, struct igt_fb *fb)
bool tiled, struct igt_fb *fb)
{
uint32_t handles[4];
uint32_t pitches[4];
@ -318,10 +434,33 @@ unsigned int igt_create_fb(int fd, int width, int height, uint32_t format,
return fb_id;
}
/**
* igt_create_color_fb:
* @fd: open i915 drm file descriptor
* @width: width of the framebuffer in pixel
* @height: height of the framebuffer in pixel
* @format: drm fourcc pixel format code
* @tiled: X-tiled or linear framebuffer
* @r: red value to use as fill color
* @g: gree value to use as fill color
* @b: blue value to use as fill color
* @fb: pointer to an #igt_fb structure
*
* This function allocates a gem buffer object suitable to back a framebuffer
* with the requested properties and then wraps it up in a drm framebuffer
* object. All metadata is stored in @fb.
*
* Compared to igt_create_fb() this function also fills the entire framebuffer
* with the given color, which is useful for some simple pipe crc based tests.
*
* Returns:
* The kms id of the created framebuffer on success or a negative error code on
* failure.
*/
unsigned int igt_create_color_fb(int fd, int width, int height,
uint32_t format, bool tiled,
double r, double g, double b,
struct igt_fb *fb /* out */)
uint32_t format, bool tiled,
double r, double g, double b,
struct igt_fb *fb /* out */)
{
unsigned int fb_id;
cairo_t *cr;
@ -345,7 +484,7 @@ static cairo_format_t drm_format_to_cairo(uint32_t drm_format)
if (f->drm_id == drm_format)
return f->cairo_id;
abort();
igt_fail(101);
}
static void __destroy_cairo_surface(void *arg)
@ -374,6 +513,19 @@ static cairo_surface_t *get_cairo_surface(int fd, struct igt_fb *fb)
return cairo_surface_reference(fb->cairo_surface);
}
/**
* igt_get_cairo_ctx:
* @fd: open i915 drm file descriptor
* @fb: pointer to an #igt_fb structure
*
* This initializes a cairo surface for @fb and then allocates a drawing context
* for it. The return cairo drawing context should be released by calling
* cairo_destroy(). This also sets a default font for drawing text on
* framebuffers.
*
* Returns:
* The created cairo drawing context.
*/
cairo_t *igt_get_cairo_ctx(int fd, struct igt_fb *fb)
{
cairo_surface_t *surface;
@ -391,6 +543,14 @@ cairo_t *igt_get_cairo_ctx(int fd, struct igt_fb *fb)
return cr;
}
/**
* @fd: open i915 drm file descriptor
* @fb: pointer to an #igt_fb structure
* @filename: target name for the png image
*
* This function stores the contents of the supplied framebuffer into a png
* image stored at @filename.
*/
void igt_write_fb_to_png(int fd, struct igt_fb *fb, const char *filename)
{
cairo_surface_t *surface;
@ -403,6 +563,15 @@ void igt_write_fb_to_png(int fd, struct igt_fb *fb, const char *filename)
igt_assert(status == CAIRO_STATUS_SUCCESS);
}
/**
* igt_remove_fb:
* @fd: open i915 drm file descriptor
* @fb: pointer to an #igt_fb structure
*
* This function releases all resources allocated in igt_create_fb() for @fb.
* Note that if this framebuffer is still in use on a primary plane the kernel
* will disable the corresponding crtc.
*/
void igt_remove_fb(int fd, struct igt_fb *fb)
{
cairo_surface_destroy(fb->cairo_surface);
@ -410,7 +579,15 @@ void igt_remove_fb(int fd, struct igt_fb *fb)
gem_close(fd, fb->gem_handle);
}
/* helpers to handle drm fourcc codes */
/**
* igt_bpp_depth_to_drm_format:
* @bpp: desired bits per pixel
* @depth: desired depth
*
* Returns:
* The rgb drm fourcc pixel format code corresponding to the given @bpp and
* @depth values. Fails hard if no match was found.
*/
uint32_t igt_bpp_depth_to_drm_format(int bpp, int depth)
{
struct format_desc_struct *f;
@ -419,10 +596,17 @@ uint32_t igt_bpp_depth_to_drm_format(int bpp, int depth)
if (f->bpp == bpp && f->depth == depth)
return f->drm_id;
abort();
igt_fail(101);
}
/* Return fb_id on success, 0 on error */
/**
* igt_drm_format_to_bpp:
* @drm_format: drm fourcc pixel format code
*
* Returns:
* The bits per pixel for the given drm fourcc pixel format code. Fails hard if
* no match was found.
*/
uint32_t igt_drm_format_to_bpp(uint32_t drm_format)
{
struct format_desc_struct *f;
@ -431,9 +615,17 @@ uint32_t igt_drm_format_to_bpp(uint32_t drm_format)
if (f->drm_id == drm_format)
return f->bpp;
abort();
igt_fail(101);
}
/**
* igt_format_str:
* @drm_format: drm fourcc pixel format code
*
* Returns:
* Human-readable fourcc pixel format code for @drm_format or "invalid" no match
* was found.
*/
const char *igt_format_str(uint32_t drm_format)
{
struct format_desc_struct *f;
@ -445,6 +637,14 @@ const char *igt_format_str(uint32_t drm_format)
return "invalid";
}
/**
* igt_get_all_formats:
* @formats: pointer to pointer to store the allocated formats array
* @format_count: pointer to integer to store the size of the allocated array
*
* This functions returns an array of all the drm fourcc codes supported by this
* library. The caller must free the allocated array again with free().
*/
void igt_get_all_formats(const uint32_t **formats, int *format_count)
{
static uint32_t *drm_formats;

View File

@ -56,17 +56,13 @@ enum igt_text_align {
align_hcenter = 0x08,
};
int igt_cairo_printf_line(cairo_t *cr, enum igt_text_align align,
double yspacing, const char *fmt, ...)
__attribute__((format (printf, 4, 5)));
unsigned int igt_create_fb(int fd, int width, int height, uint32_t format,
bool tiled, struct igt_fb *fb);
unsigned int igt_create_color_fb(int fd, int width, int height,
uint32_t format, bool tiled,
double r, double g, double b,
struct igt_fb *fb /* out */);
void igt_remove_fb(int fd, struct igt_fb *fb_info);
void igt_remove_fb(int fd, struct igt_fb *fb);
/* cairo-based painting */
cairo_t *igt_get_cairo_ctx(int fd, struct igt_fb *fb);
@ -80,6 +76,9 @@ void igt_paint_test_pattern(cairo_t *cr, int width, int height);
void igt_paint_image(cairo_t *cr, const char *filename,
int dst_x, int dst_y, int dst_width, int dst_height);
void igt_write_fb_to_png(int fd, struct igt_fb *fb, const char *filename);
int igt_cairo_printf_line(cairo_t *cr, enum igt_text_align align,
double yspacing, const char *fmt, ...)
__attribute__((format (printf, 4, 5)));
/* helpers to handle drm fourcc codes */
uint32_t igt_bpp_depth_to_drm_format(int bpp, int depth);