vo_opengl: refactor into vo_gpu

This is done in several steps:

1. refactor MPGLContext -> struct ra_ctx
2. move GL-specific stuff in vo_opengl into opengl/context.c
3. generalize context creation to support other APIs, and add --gpu-api
4. rename all of the --opengl- options that are no longer opengl-specific
5. move all of the stuff from opengl/* that isn't GL-specific into gpu/
   (note: opengl/gl_utils.h became opengl/utils.h)
6. rename vo_opengl to vo_gpu
7. to handle window screenshots, the short-term approach was to just add
   it to ra_swchain_fns. Long term (and for vulkan) this has to be moved to
   ra itself (and vo_gpu altered to compensate), but this was a stop-gap
   measure to prevent this commit from getting too big
8. move ra->fns->flush to ra_gl_ctx instead
9. some other minor changes that I've probably already forgotten

Note: This is one half of a major refactor, the other half of which is
provided by rossy's following commit. This commit enables support for
all linux platforms, while his version enables support for all non-linux
platforms.

Note 2: vo_opengl_cb.c also re-uses ra_gl_ctx so it benefits from the
--opengl- options like --opengl-early-flush, --opengl-finish etc. Should
be a strict superset of the old functionality.

Disclaimer: Since I have no way of compiling mpv on all platforms, some
of these ports were done blindly. Specifically, the blind ports included
context_mali_fbdev.c and context_rpi.c. Since they're both based on
egl_helpers, the port should have gone smoothly without any major
changes required. But if somebody complains about a compile error on
those platforms (assuming anybody actually uses them), you know where to
complain.

1 files changed, 120 insertions, 0 deletions

diff --git a/video/out/gpu/utils.h b/video/out/gpu/utils.h
new file mode 100644
index 0000000000..04695f8085
--- /dev/null
+++ b/video/out/gpu/utils.h
@@ -0,0 +1,120 @@
+#pragma once
+
+#include <stdbool.h>
+#include <math.h>
+
+#include "ra.h"
+
+// A 3x2 matrix, with the translation part separate.
+struct gl_transform {
+    // row-major, e.g. in mathematical notation:
+    //  | m[0][0] m[0][1] |
+    //  | m[1][0] m[1][1] |
+    float m[2][2];
+    float t[2];
+};
+
+static const struct gl_transform identity_trans = {
+    .m = {{1.0, 0.0}, {0.0, 1.0}},
+    .t = {0.0, 0.0},
+};
+
+void gl_transform_ortho(struct gl_transform *t, float x0, float x1,
+                        float y0, float y1);
+
+// This treats m as an affine transformation, in other words m[2][n] gets
+// added to the output.
+static inline void gl_transform_vec(struct gl_transform t, float *x, float *y)
+{
+    float vx = *x, vy = *y;
+    *x = vx * t.m[0][0] + vy * t.m[0][1] + t.t[0];
+    *y = vx * t.m[1][0] + vy * t.m[1][1] + t.t[1];
+}
+
+struct mp_rect_f {
+    float x0, y0, x1, y1;
+};
+
+// Semantic equality (fuzzy comparison)
+static inline bool mp_rect_f_seq(struct mp_rect_f a, struct mp_rect_f b)
+{
+    return fabs(a.x0 - b.x0) < 1e-6 && fabs(a.x1 - b.x1) < 1e-6 &&
+           fabs(a.y0 - b.y0) < 1e-6 && fabs(a.y1 - b.y1) < 1e-6;
+}
+
+static inline void gl_transform_rect(struct gl_transform t, struct mp_rect_f *r)
+{
+    gl_transform_vec(t, &r->x0, &r->y0);
+    gl_transform_vec(t, &r->x1, &r->y1);
+}
+
+static inline bool gl_transform_eq(struct gl_transform a, struct gl_transform b)
+{
+    for (int x = 0; x < 2; x++) {
+        for (int y = 0; y < 2; y++) {
+            if (a.m[x][y] != b.m[x][y])
+                return false;
+        }
+    }
+
+    return a.t[0] == b.t[0] && a.t[1] == b.t[1];
+}
+
+void gl_transform_trans(struct gl_transform t, struct gl_transform *x);
+
+struct fbodst {
+    struct ra_tex *tex;
+    bool flip; // mirror vertically
+};
+
+void gl_transform_ortho_fbodst(struct gl_transform *t, struct fbodst fbo);
+
+// A pool of buffers, which can grow as needed
+struct ra_buf_pool {
+    struct ra_buf_params current_params;
+    struct ra_buf **buffers;
+    int num_buffers;
+    int index;
+};
+
+void ra_buf_pool_uninit(struct ra *ra, struct ra_buf_pool *pool);
+
+// Note: params->initial_data is *not* supported
+struct ra_buf *ra_buf_pool_get(struct ra *ra, struct ra_buf_pool *pool,
+                               const struct ra_buf_params *params);
+
+// Helper that wraps ra_tex_upload using texture upload buffers to ensure that
+// params->buf is always set. This is intended for RA-internal usage.
+bool ra_tex_upload_pbo(struct ra *ra, struct ra_buf_pool *pbo,
+                       const struct ra_tex_upload_params *params);
+
+// Layout rules for GLSL's packing modes
+struct ra_layout std140_layout(struct ra_renderpass_input *inp);
+struct ra_layout std430_layout(struct ra_renderpass_input *inp);
+
+struct fbotex {
+    struct ra *ra;
+    struct ra_tex *tex;
+    int lw, lh; // logical (configured) size, <= than texture size
+    struct fbodst fbo;
+};
+
+void fbotex_uninit(struct fbotex *fbo);
+bool fbotex_change(struct fbotex *fbo, struct ra *ra, struct mp_log *log,
+                   int w, int h, const struct ra_format *fmt, int flags);
+#define FBOTEX_FUZZY_W 1
+#define FBOTEX_FUZZY_H 2
+#define FBOTEX_FUZZY (FBOTEX_FUZZY_W | FBOTEX_FUZZY_H)
+
+// A wrapper around ra_timer that does result pooling, averaging etc.
+struct timer_pool;
+
+struct timer_pool *timer_pool_create(struct ra *ra);
+void timer_pool_destroy(struct timer_pool *pool);
+void timer_pool_start(struct timer_pool *pool);
+void timer_pool_stop(struct timer_pool *pool);
+struct mp_pass_perf timer_pool_measure(struct timer_pool *pool);
+
+// print a multi line string with line numbers (e.g. for shader sources)
+// log, lev: module and log level, as in mp_msg()
+void mp_log_source(struct mp_log *log, int lev, const char *src);