render: introduce blend mode

Allow callers to pick the blend mode when rendering a rect. The
"none" mode can be used to disable blending and clear rects.
This commit is contained in:
Simon Ser 2023-05-02 21:32:51 +02:00
parent 6b7d1d732a
commit a93fc8afd6
3 changed files with 34 additions and 2 deletions

View File

@ -177,6 +177,16 @@ struct wlr_render_pass *wlr_renderer_begin_buffer_pass(
*/
bool wlr_render_pass_submit(struct wlr_render_pass *render_pass);
/**
* Blend modes.
*/
enum wlr_render_blend_mode {
/* Pre-multiplied alpha (default) */
WLR_RENDER_BLEND_MODE_PREMULTIPLIED,
/* Blending is disabled */
WLR_RENDER_BLEND_MODE_NONE,
};
struct wlr_render_texture_options {
/* Source texture */
struct wlr_texture *texture;
@ -215,6 +225,8 @@ struct wlr_render_rect_options {
struct wlr_render_color color;
/* Clip region, leave NULL to disable clipping */
const pixman_region32_t *clip;
/* Blend mode */
enum wlr_render_blend_mode blend_mode;
};
/**

View File

@ -134,6 +134,8 @@ static void legacy_add_rect(struct wlr_render_pass *wlr_pass,
pixman_region32_t clip;
get_clip_region(pass, options->clip, &clip);
pixman_region32_intersect_rect(&clip, &clip,
options->box.x, options->box.y, options->box.width, options->box.height);
float color[4] = {
options->color.r,
@ -146,7 +148,14 @@ static void legacy_add_rect(struct wlr_render_pass *wlr_pass,
const pixman_box32_t *rects = pixman_region32_rectangles(&clip, &rects_len);
for (int i = 0; i < rects_len; i++) {
scissor(pass->renderer, &rects[i]);
wlr_render_quad_with_matrix(pass->renderer, color, matrix);
switch (options->blend_mode) {
case WLR_RENDER_BLEND_MODE_PREMULTIPLIED:
wlr_render_quad_with_matrix(pass->renderer, color, matrix);
break;
case WLR_RENDER_BLEND_MODE_NONE:
wlr_renderer_clear(pass->renderer, color);
break;
}
}
wlr_renderer_scissor(pass->renderer, NULL);

View File

@ -143,6 +143,17 @@ static void render_pass_add_rect(struct wlr_render_pass *wlr_pass,
struct wlr_pixman_buffer *buffer = pass->buffer;
struct wlr_box box = options->box;
pixman_op_t op = 0;
switch (options->blend_mode) {
case WLR_RENDER_BLEND_MODE_PREMULTIPLIED:
op = options->color.a == 1 ? PIXMAN_OP_SRC : PIXMAN_OP_OVER;
break;
case WLR_RENDER_BLEND_MODE_NONE:
op = PIXMAN_OP_SRC;
break;
}
assert(op != 0);
struct pixman_color color = {
.red = options->color.r * 0xFFFF,
.green = options->color.g * 0xFFFF,
@ -153,7 +164,7 @@ static void render_pass_add_rect(struct wlr_render_pass *wlr_pass,
pixman_image_t *fill = pixman_image_create_solid_fill(&color);
pixman_image_set_clip_region32(buffer->image, (pixman_region32_t *)options->clip);
pixman_image_composite32(PIXMAN_OP_OVER, fill, NULL, buffer->image,
pixman_image_composite32(op, fill, NULL, buffer->image,
0, 0, 0, 0, box.x, box.y, box.width, box.height);
pixman_image_set_clip_region32(buffer->image, NULL);