vo_opengl: be explicit about IMG_RW

Both vulkan and opengl distinguish between rendering to an image and
using an image as a storage attachment. So make this an explicit
capability instead of lumping it in with render_dst. (That way we could
support, for example, using an image as a storage attachment without
requiring a framebuffer)

The real reason for this change is that you can directly use the output
FBO as a storage attachment on vulkan but you can't on opengl, which
makes this param structly separate from render_dst.

3 files changed, 13 insertions, 8 deletions

diff --git a/video/out/opengl/ra.h b/video/out/opengl/ra.h
index f2b41256db..f09fa6c861 100644
--- a/video/out/opengl/ra.h
+++ b/video/out/opengl/ra.h
@@ -90,6 +90,7 @@ struct ra_tex_params {
     const struct ra_format *format;
     bool render_src;        // must be useable as source texture in a shader
     bool render_dst;        // must be useable as target texture in a shader
+    bool storage_dst;       // must be usable as a storage image (RA_VARTYPE_IMG_W)
     bool blit_src;          // must be usable as a blit source
     bool blit_dst;          // must be usable as a blit destination
     bool host_mutable;      // texture may be updated with tex_upload
@@ -170,6 +171,7 @@ enum ra_vartype {
                                 // ra_tex.params.render_src must be true
     RA_VARTYPE_IMG_W,           // C: ra_tex*, GLSL: various image types
                                 // write-only (W) image for compute shaders
+                                // ra_tex.params.storage_dst must be true
     RA_VARTYPE_BYTE_UNORM,      // C: uint8_t, GLSL: int, vec* (vertex data only)
     RA_VARTYPE_BUF_RW,          // C: ra_buf*, GLSL: buffer block
 };
diff --git a/video/out/opengl/ra_gl.c b/video/out/opengl/ra_gl.c
index e31948c2b1..d9c7205815 100644
--- a/video/out/opengl/ra_gl.c
+++ b/video/out/opengl/ra_gl.c
@@ -893,18 +893,20 @@ static void update_uniform(struct ra *ra, struct ra_renderpass *pass,
         }
         break;
     }
-    case RA_VARTYPE_IMG_W: /* fall through */
+    case RA_VARTYPE_IMG_W: {
+        struct ra_tex *tex = *(struct ra_tex **)val->data;
+        struct ra_tex_gl *tex_gl = tex->priv;
+        assert(tex->params.storage_dst);
+        gl->BindImageTexture(input->binding, tex_gl->texture, 0, GL_FALSE, 0,
+                             GL_WRITE_ONLY, tex_gl->internal_format);
+        break;
+    }
     case RA_VARTYPE_TEX: {
         struct ra_tex *tex = *(struct ra_tex **)val->data;
         struct ra_tex_gl *tex_gl = tex->priv;
         assert(tex->params.render_src);
-        if (input->type == RA_VARTYPE_TEX) {
-            gl->ActiveTexture(GL_TEXTURE0 + input->binding);
-            gl->BindTexture(tex_gl->target, tex_gl->texture);
-        } else {
-            gl->BindImageTexture(input->binding, tex_gl->texture, 0, GL_FALSE, 0,
-                                 GL_WRITE_ONLY, tex_gl->internal_format);
-        }
+        gl->ActiveTexture(GL_TEXTURE0 + input->binding);
+        gl->BindTexture(tex_gl->target, tex_gl->texture);
         break;
     }
     case RA_VARTYPE_BUF_RW: {
diff --git a/video/out/opengl/utils.c b/video/out/opengl/utils.c
index e7fce62662..cdd8903bc5 100644
--- a/video/out/opengl/utils.c
+++ b/video/out/opengl/utils.c
@@ -174,6 +174,7 @@ bool fbotex_change(struct fbotex *fbo, struct ra *ra, struct mp_log *log,
         .src_linear = true,
         .render_src = true,
         .render_dst = true,
+        .storage_dst = true,
         .blit_src = true,
     };