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, 327 insertions, 0 deletions

diff --git a/video/out/gpu/ra.c b/video/out/gpu/ra.c
new file mode 100644
index 0000000000..ef1de54d1a
--- /dev/null
+++ b/video/out/gpu/ra.c
@@ -0,0 +1,327 @@
+#include "common/common.h"
+#include "common/msg.h"
+#include "video/img_format.h"
+
+#include "ra.h"
+
+struct ra_tex *ra_tex_create(struct ra *ra, const struct ra_tex_params *params)
+{
+    return ra->fns->tex_create(ra, params);
+}
+
+void ra_tex_free(struct ra *ra, struct ra_tex **tex)
+{
+    if (*tex)
+        ra->fns->tex_destroy(ra, *tex);
+    *tex = NULL;
+}
+
+struct ra_buf *ra_buf_create(struct ra *ra, const struct ra_buf_params *params)
+{
+    return ra->fns->buf_create(ra, params);
+}
+
+void ra_buf_free(struct ra *ra, struct ra_buf **buf)
+{
+    if (*buf)
+        ra->fns->buf_destroy(ra, *buf);
+    *buf = NULL;
+}
+
+void ra_free(struct ra **ra)
+{
+    if (*ra)
+        (*ra)->fns->destroy(*ra);
+    talloc_free(*ra);
+    *ra = NULL;
+}
+
+size_t ra_vartype_size(enum ra_vartype type)
+{
+    switch (type) {
+    case RA_VARTYPE_INT:        return sizeof(int);
+    case RA_VARTYPE_FLOAT:      return sizeof(float);
+    case RA_VARTYPE_BYTE_UNORM: return 1;
+    default: return 0;
+    }
+}
+
+struct ra_layout ra_renderpass_input_layout(struct ra_renderpass_input *input)
+{
+    size_t el_size = ra_vartype_size(input->type);
+    if (!el_size)
+        return (struct ra_layout){0};
+
+    // host data is always tightly packed
+    return (struct ra_layout) {
+        .align  = 1,
+        .stride = el_size * input->dim_v,
+        .size   = el_size * input->dim_v * input->dim_m,
+    };
+}
+
+static struct ra_renderpass_input *dup_inputs(void *ta_parent,
+            const struct ra_renderpass_input *inputs, int num_inputs)
+{
+    struct ra_renderpass_input *res =
+        talloc_memdup(ta_parent, (void *)inputs, num_inputs * sizeof(inputs[0]));
+    for (int n = 0; n < num_inputs; n++)
+        res[n].name = talloc_strdup(res, res[n].name);
+    return res;
+}
+
+// Return a newly allocated deep-copy of params.
+struct ra_renderpass_params *ra_renderpass_params_copy(void *ta_parent,
+        const struct ra_renderpass_params *params)
+{
+    struct ra_renderpass_params *res = talloc_ptrtype(ta_parent, res);
+    *res = *params;
+    res->inputs = dup_inputs(res, res->inputs, res->num_inputs);
+    res->vertex_attribs =
+        dup_inputs(res, res->vertex_attribs, res->num_vertex_attribs);
+    res->cached_program = bstrdup(res, res->cached_program);
+    res->vertex_shader = talloc_strdup(res, res->vertex_shader);
+    res->frag_shader = talloc_strdup(res, res->frag_shader);
+    res->compute_shader = talloc_strdup(res, res->compute_shader);
+    return res;
+};
+
+
+// Return whether this is a tightly packed format with no external padding and
+// with the same bit size/depth in all components, and the shader returns
+// components in the same order as in memory.
+static bool ra_format_is_regular(const struct ra_format *fmt)
+{
+    if (!fmt->pixel_size || !fmt->num_components || !fmt->ordered)
+        return false;
+    for (int n = 1; n < fmt->num_components; n++) {
+        if (fmt->component_size[n] != fmt->component_size[0] ||
+            fmt->component_depth[n] != fmt->component_depth[0])
+            return false;
+    }
+    if (fmt->component_size[0] * fmt->num_components != fmt->pixel_size * 8)
+        return false;
+    return true;
+}
+
+// Return a regular filterable format using RA_CTYPE_UNORM.
+const struct ra_format *ra_find_unorm_format(struct ra *ra,
+                                             int bytes_per_component,
+                                             int n_components)
+{
+    for (int n = 0; n < ra->num_formats; n++) {
+        const struct ra_format *fmt = ra->formats[n];
+        if (fmt->ctype == RA_CTYPE_UNORM && fmt->num_components == n_components &&
+            fmt->pixel_size == bytes_per_component * n_components &&
+            fmt->component_depth[0] == bytes_per_component * 8 &&
+            fmt->linear_filter && ra_format_is_regular(fmt))
+            return fmt;
+    }
+    return NULL;
+}
+
+// Return a regular format using RA_CTYPE_UINT.
+const struct ra_format *ra_find_uint_format(struct ra *ra,
+                                            int bytes_per_component,
+                                            int n_components)
+{
+    for (int n = 0; n < ra->num_formats; n++) {
+        const struct ra_format *fmt = ra->formats[n];
+        if (fmt->ctype == RA_CTYPE_UINT && fmt->num_components == n_components &&
+            fmt->pixel_size == bytes_per_component * n_components &&
+            fmt->component_depth[0] == bytes_per_component * 8 &&
+            ra_format_is_regular(fmt))
+            return fmt;
+    }
+    return NULL;
+}
+
+// Find a float format of any precision that matches the C type of the same
+// size for upload.
+// May drop bits from the mantissa (such as selecting float16 even if
+// bytes_per_component == 32); prefers possibly faster formats first.
+static const struct ra_format *ra_find_float_format(struct ra *ra,
+                                                    int bytes_per_component,
+                                                    int n_components)
+{
+    // Assumes ra_format are ordered by performance.
+    // The >=16 check is to avoid catching fringe formats.
+    for (int n = 0; n < ra->num_formats; n++) {
+        const struct ra_format *fmt = ra->formats[n];
+        if (fmt->ctype == RA_CTYPE_FLOAT && fmt->num_components == n_components &&
+            fmt->pixel_size == bytes_per_component * n_components &&
+            fmt->component_depth[0] >= 16 &&
+            fmt->linear_filter && ra_format_is_regular(fmt))
+            return fmt;
+    }
+    return NULL;
+}
+
+// Return a filterable regular format that uses at least float16 internally, and
+// uses a normal C float for transfer on the CPU side. (This is just so we don't
+// need 32->16 bit conversion on CPU, which would be messy.)
+const struct ra_format *ra_find_float16_format(struct ra *ra, int n_components)
+{
+    return ra_find_float_format(ra, sizeof(float), n_components);
+}
+
+const struct ra_format *ra_find_named_format(struct ra *ra, const char *name)
+{
+    for (int n = 0; n < ra->num_formats; n++) {
+        const struct ra_format *fmt = ra->formats[n];
+        if (strcmp(fmt->name, name) == 0)
+            return fmt;
+    }
+    return NULL;
+}
+
+// Like ra_find_unorm_format(), but if no fixed point format is available,
+// return an unsigned integer format.
+static const struct ra_format *find_plane_format(struct ra *ra, int bytes,
+                                                 int n_channels,
+                                                 enum mp_component_type ctype)
+{
+    switch (ctype) {
+    case MP_COMPONENT_TYPE_UINT: {
+        const struct ra_format *f = ra_find_unorm_format(ra, bytes, n_channels);
+        if (f)
+            return f;
+        return ra_find_uint_format(ra, bytes, n_channels);
+    }
+    case MP_COMPONENT_TYPE_FLOAT:
+        return ra_find_float_format(ra, bytes, n_channels);
+    default: return NULL;
+    }
+}
+
+// Put a mapping of imgfmt to texture formats into *out. Basically it selects
+// the correct texture formats needed to represent an imgfmt in a shader, with
+// textures using the same memory organization as on the CPU.
+// Each plane is represented by a texture, and each texture has a RGBA
+// component order. out->components describes the meaning of them.
+// May return integer formats for >8 bit formats, if the driver has no
+// normalized 16 bit formats.
+// Returns false (and *out is not touched) if no format found.
+bool ra_get_imgfmt_desc(struct ra *ra, int imgfmt, struct ra_imgfmt_desc *out)
+{
+    struct ra_imgfmt_desc res = {0};
+
+    struct mp_regular_imgfmt regfmt;
+    if (mp_get_regular_imgfmt(&regfmt, imgfmt)) {
+        enum ra_ctype ctype = RA_CTYPE_UNKNOWN;
+        res.num_planes = regfmt.num_planes;
+        res.component_bits = regfmt.component_size * 8;
+        res.component_pad = regfmt.component_pad;
+        for (int n = 0; n < regfmt.num_planes; n++) {
+            struct mp_regular_imgfmt_plane *plane = &regfmt.planes[n];
+            res.planes[n] = find_plane_format(ra, regfmt.component_size,
+                                              plane->num_components,
+                                              regfmt.component_type);
+            if (!res.planes[n])
+                return false;
+            for (int i = 0; i < plane->num_components; i++)
+                res.components[n][i] = plane->components[i];
+            // Dropping LSBs when shifting will lead to dropped MSBs.
+            if (res.component_bits > res.planes[n]->component_depth[0] &&
+                res.component_pad < 0)
+                return false;
+            // Renderer restriction, but actually an unwanted corner case.
+            if (ctype != RA_CTYPE_UNKNOWN && ctype != res.planes[n]->ctype)
+                return false;
+            ctype = res.planes[n]->ctype;
+        }
+        res.chroma_w = regfmt.chroma_w;
+        res.chroma_h = regfmt.chroma_h;
+        goto supported;
+    }
+
+    for (int n = 0; n < ra->num_formats; n++) {
+        if (imgfmt && ra->formats[n]->special_imgfmt == imgfmt) {
+            res = *ra->formats[n]->special_imgfmt_desc;
+            goto supported;
+        }
+    }
+
+    // Unsupported format
+    return false;
+
+supported:
+
+    *out = res;
+    return true;
+}
+
+void ra_dump_tex_formats(struct ra *ra, int msgl)
+{
+    if (!mp_msg_test(ra->log, msgl))
+        return;
+    MP_MSG(ra, msgl, "Texture formats:\n");
+    MP_MSG(ra, msgl, "  NAME       COMP*TYPE SIZE        DEPTH PER COMP.\n");
+    for (int n = 0; n < ra->num_formats; n++) {
+        const struct ra_format *fmt = ra->formats[n];
+        const char *ctype = "unknown";
+        switch (fmt->ctype) {
+        case RA_CTYPE_UNORM:    ctype = "unorm";    break;
+        case RA_CTYPE_UINT:     ctype = "uint ";    break;
+        case RA_CTYPE_FLOAT:    ctype = "float";    break;
+        }
+        char cl[40] = "";
+        for (int i = 0; i < fmt->num_components; i++) {
+            mp_snprintf_cat(cl, sizeof(cl), "%s%d", i ? " " : "",
+                            fmt->component_size[i]);
+            if (fmt->component_size[i] != fmt->component_depth[i])
+                mp_snprintf_cat(cl, sizeof(cl), "/%d", fmt->component_depth[i]);
+        }
+        MP_MSG(ra, msgl, "  %-10s %d*%s %3dB %s %s %s {%s}\n", fmt->name,
+               fmt->num_components, ctype, fmt->pixel_size,
+               fmt->luminance_alpha ? "LA" : "  ",
+               fmt->linear_filter ? "LF" : "  ",
+               fmt->renderable ? "CR" : "  ", cl);
+    }
+    MP_MSG(ra, msgl, " LA = LUMINANCE_ALPHA hack format\n");
+    MP_MSG(ra, msgl, " LF = linear filterable\n");
+    MP_MSG(ra, msgl, " CR = can be used for render targets\n");
+}
+
+void ra_dump_imgfmt_desc(struct ra *ra, const struct ra_imgfmt_desc *desc,
+                         int msgl)
+{
+    char pl[80] = "";
+    char pf[80] = "";
+    for (int n = 0; n < desc->num_planes; n++) {
+        if (n > 0) {
+            mp_snprintf_cat(pl, sizeof(pl), "/");
+            mp_snprintf_cat(pf, sizeof(pf), "/");
+        }
+        char t[5] = {0};
+        for (int i = 0; i < 4; i++)
+            t[i] = "_rgba"[desc->components[n][i]];
+        for (int i = 3; i > 0 && t[i] == '_'; i--)
+            t[i] = '\0';
+        mp_snprintf_cat(pl, sizeof(pl), "%s", t);
+        mp_snprintf_cat(pf, sizeof(pf), "%s", desc->planes[n]->name);
+    }
+    MP_MSG(ra, msgl, "%d planes %dx%d %d/%d [%s] (%s)\n",
+           desc->num_planes, desc->chroma_w, desc->chroma_h,
+           desc->component_bits, desc->component_pad, pf, pl);
+}
+
+void ra_dump_img_formats(struct ra *ra, int msgl)
+{
+    if (!mp_msg_test(ra->log, msgl))
+        return;
+    MP_MSG(ra, msgl, "Image formats:\n");
+    for (int imgfmt = IMGFMT_START; imgfmt < IMGFMT_END; imgfmt++) {
+        const char *name = mp_imgfmt_to_name(imgfmt);
+        if (strcmp(name, "unknown") == 0)
+            continue;
+        MP_MSG(ra, msgl, "  %s", name);
+        struct ra_imgfmt_desc desc;
+        if (ra_get_imgfmt_desc(ra, imgfmt, &desc)) {
+            MP_MSG(ra, msgl, " => ");
+            ra_dump_imgfmt_desc(ra, &desc, msgl);
+        } else {
+            MP_MSG(ra, msgl, "\n");
+        }
+    }
+}