vtgl

Commit: 2800fa1a5f6cd085e8fee0ac45a1b0967dea22a9
Parent: e1ea2736fea8fc6257af53e5fcef71d0c8d5841d
Author: Randy Palamar
Date:   Mon, 21 Oct 2024 09:07:36 -0600

only refill/upload ssbo when the contents would change

Diffstat:
M
util.h
 | 
1
+
M
vtgl.c
 | 
32
++++++++++++++++++--------------

2 files changed, 19 insertions(+), 14 deletions(-)
diff --git a/util.h b/util.h
@@ -197,6 +197,7 @@ enum gl_flags {
 	NEEDS_RESIZE           = 1 << 0,
 	NEEDS_REFILL           = 1 << 1,
 	NEEDS_FULL_REFILL      = 1 << 2,
+	UPDATE_RENDER_BUFFER   = 1 << 3,
 
 	UPDATE_RENDER_UNIFORMS = 1 << 27,
 	UPDATE_POST_UNIFORMS   = 1 << 28,
diff --git a/vtgl.c b/vtgl.c
@@ -398,6 +398,7 @@ update_selection(Term *t)
 		}
 	}
 	sel->range   = normalize_range(sel->range);
+	t->gl.flags |= UPDATE_RENDER_BUFFER;
 }
 
 KEYBIND_FN(copy)
@@ -763,15 +764,27 @@ do_terminal(Term *t, f32 dt)
 		t->gl.flags  |= NEEDS_REFILL;
 	}
 
-	if (t->gl.flags & (NEEDS_REFILL|NEEDS_FULL_REFILL))
+	if (t->gl.flags & (NEEDS_REFILL|NEEDS_FULL_REFILL)) {
 		blit_lines(t, t->arena_for_frame, parsed_lines);
+		t->gl.flags |= UPDATE_RENDER_BUFFER;
+	}
 
 	update_selection(t);
 
-	u32 cell_count = t->size.h * t->size.w;
-	/* NOTE: this must be done every frame since we have time varying parameters */
-	RenderCell *render_buf = alloc(&t->arena_for_frame, RenderCell, cell_count);
-	render_framebuffer(t, render_buf);
+	glUseProgram(t->gl.programs[SHADER_RENDER]);
+	glBindFramebuffer(GL_FRAMEBUFFER, t->gl.fb);
+	clear_colour(t->gl.mode & WIN_MODE_REVERSE);
+
+	if (t->gl.flags & UPDATE_RENDER_BUFFER) {
+		u32 cell_count = t->size.h * t->size.w;
+		RenderCell *render_buf = alloc(&t->arena_for_frame, RenderCell, cell_count);
+		render_framebuffer(t, render_buf);
+
+		glBindBuffer(GL_SHADER_STORAGE_BUFFER, t->gl.render_shader_ssbo);
+		glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, t->gl.render_shader_ssbo);
+		glBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, cell_count * sizeof(*render_buf), render_buf);
+		t->gl.flags &= ~UPDATE_RENDER_BUFFER;
+	}
 
 	ShaderParameters *sp = &t->gl.shader_parameters;
 	sp->blink_parameter += 2 * PI * g_blink_speed * dt_for_frame;
@@ -781,21 +794,12 @@ do_terminal(Term *t, f32 dt)
 	sp->underline_min = (u32)(0.94 * t->fa.info.h);
 	sp->underline_max = t->fa.info.h;
 
-	glUseProgram(t->gl.programs[SHADER_RENDER]);
-	glBindFramebuffer(GL_FRAMEBUFFER, t->gl.fb);
-
-	clear_colour(t->gl.mode & WIN_MODE_REVERSE);
-
 	glUniform2fv(t->gl.render.vertscale, 1, t->gl.window_size.E);
 
 	glBindBuffer(GL_UNIFORM_BUFFER, t->gl.render_shader_ubo);
 	glBindBufferBase(GL_UNIFORM_BUFFER, 0, t->gl.render_shader_ubo);
 	glBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(*sp), sp);
 
-	glBindBuffer(GL_SHADER_STORAGE_BUFFER, t->gl.render_shader_ssbo);
-	glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, t->gl.render_shader_ssbo);
-	glBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, cell_count * sizeof(*render_buf), render_buf);
-
 	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 
 	static f32 param = 0;