[vulkan] Support clipping rectangles via scissor

Seems to work well. The other renderers have stubs because I don't feel
like implementing clipping for them. The gl and glsl wouldn't be too
difficult (need to handle the draw queues), but sw needs a fair bit of
work and I'm not sure it's worth the effort.

include/QF/GL/qf_draw.h

@@ -61,6 +61,8 @@ void gl_Draw_SubPic(int x, int y, struct qpic_s *pic,
 					  int srcx, int srcy, int width, int height);
 int gl_Draw_AddFont (struct font_s *font);
 void gl_Draw_Glyph (int x, int y, int fontid, int glyphid, int c);
+void gl_Draw_SetClip (int x, int y, int w, int h);
+void gl_Draw_ResetClip (void);
 
 void GL_Set2D (void);
 void GL_Set2DScaled (void);

include/QF/GLSL/qf_draw.h

@@ -62,6 +62,8 @@ void glsl_Draw_SubPic(int x, int y, struct qpic_s *pic,
 					  int srcx, int srcy, int width, int height);
 int glsl_Draw_AddFont (struct font_s *font);
 void glsl_Draw_Glyph (int x, int y, int fontid, int glyphid, int c);
+void glsl_Draw_SetClip (int x, int y, int w, int h);
+void glsl_Draw_ResetClip (void);
 
 void GLSL_Set2D (void);
 void GLSL_Set2DScaled (void);

include/QF/Vulkan/qf_draw.h

@@ -82,6 +82,8 @@ void Vulkan_Draw_SubPic(int x, int y, struct qpic_s *pic,
 int Vulkan_Draw_AddFont (struct font_s *font, struct vulkan_ctx_s *ctx);
 void Vulkan_Draw_Glyph (int x, int y, int fontid, int glyphid, int c,
 						struct vulkan_ctx_s *ctx);
+void Vulkan_Draw_SetClip (int x, int y, int w, int h, struct vulkan_ctx_s *ctx);
+void Vulkan_Draw_ResetClip (struct vulkan_ctx_s *ctx);
 
 void Vulkan_LineGraph (int x, int y, int *h_vals, int count, int height,
 					   struct vulkan_ctx_s *ctx);

include/QF/draw.h

@@ -279,6 +279,8 @@ void Draw_SubPic(int x, int y, qpic_t *pic, int srcx, int srcy, int width, int h
 struct font_s;
 int Draw_AddFont (struct font_s *font);
 void Draw_Glyph (int x, int y, int fontid, int glyphid, int c);
+void Draw_SetClip (int x, int y, int w, int h);
+void Draw_ResetClip (void);
 
 ///@}
 

include/QF/plugin/vid_render.h

@@ -116,6 +116,8 @@ typedef struct vid_render_funcs_s {
 	void (*Draw_SubPic) (int x, int y, qpic_t *pic, int srcx, int srcy, int width, int height);
 	int (*Draw_AddFont) (struct font_s *font);
 	void (*Draw_Glyph) (int x, int y, int fontid, int glyphid, int c);
+	void (*Draw_SetClip) (int x, int y, int w, int h);
+	void (*Draw_ResetClip) (void);
 
 	struct psystem_s *(*ParticleSystem) (void);
 	struct psystem_s *(*TrailSystem) (void);

libs/video/renderer/gl/gl_draw.c

@@ -1131,3 +1131,13 @@ gl_Draw_Glyph (int x, int y, int fontid, int glyphid, int c)
 	qfglEnd ();
 	qfglColor4ubv (color_white);
 }
+
+void
+gl_Draw_SetClip (int x, int y, int w, int h)
+{
+}
+
+void
+gl_Draw_ResetClip (void)
+{
+}

libs/video/renderer/glsl/glsl_draw.c

@@ -1111,3 +1111,13 @@ glsl_Draw_Glyph (int x, int y, int fontid, int glyphid, int c)
 	QuatCopy (color, verts[4].color);
 	QuatCopy (color, verts[5].color);
 }
+
+void
+glsl_Draw_SetClip (int x, int y, int w, int h)
+{
+}
+
+void
+glsl_Draw_ResetClip (void)
+{
+}

libs/video/renderer/sw/draw.c

@@ -1096,3 +1096,13 @@ Draw_Glyph (int x, int y, int fontid, int glyphid, int c)
 		dst += d_rowbytes;
 	}
 }
+
+void
+Draw_SetClip (int x, int y, int w, int h)
+{
+}
+
+void
+Draw_ResetClip (void)
+{
+}

libs/video/renderer/vid_render_gl.c

@@ -529,6 +529,8 @@ vid_render_funcs_t gl_vid_render_funcs = {
 	.Draw_SubPic            = gl_Draw_SubPic,
 	.Draw_AddFont           = gl_Draw_AddFont,
 	.Draw_Glyph             = gl_Draw_Glyph,
+	.Draw_SetClip           = gl_Draw_SetClip,
+	.Draw_ResetClip         = gl_Draw_ResetClip,
 
 	.ParticleSystem   = gl_ParticleSystem,
 	.R_Init           = gl_R_Init,

libs/video/renderer/vid_render_glsl.c

@@ -475,6 +475,8 @@ vid_render_funcs_t glsl_vid_render_funcs = {
 	.Draw_SubPic            = glsl_Draw_SubPic,
 	.Draw_AddFont           = glsl_Draw_AddFont,
 	.Draw_Glyph             = glsl_Draw_Glyph,
+	.Draw_SetClip           = glsl_Draw_SetClip,
+	.Draw_ResetClip         = glsl_Draw_ResetClip,
 
 	.ParticleSystem   = glsl_ParticleSystem,
 	.TrailSystem      = glsl_TrailSystem,

libs/video/renderer/vid_render_sw.c

@@ -485,6 +485,8 @@ vid_render_funcs_t sw_vid_render_funcs = {
 	.Draw_SubPic            = Draw_SubPic,
 	.Draw_AddFont           = Draw_AddFont,
 	.Draw_Glyph             = Draw_Glyph,
+	.Draw_SetClip           = Draw_SetClip,
+	.Draw_ResetClip         = Draw_ResetClip,
 
 	.ParticleSystem   = sw_ParticleSystem,
 	.R_Init           = sw_R_Init,

libs/video/renderer/vid_render_vulkan.c

@@ -327,6 +327,18 @@ vulkan_Draw_Glyph (int x, int y, int fontid, int glyphid, int c)
 	Vulkan_Draw_Glyph (x, y, fontid, glyphid, c, vulkan_ctx);
 }
 
+static void
+vulkan_Draw_SetClip (int x, int y, int w, int h)
+{
+	Vulkan_Draw_SetClip (x, y, w, h, vulkan_ctx);
+}
+
+static void
+vulkan_Draw_ResetClip (void)
+{
+	Vulkan_Draw_ResetClip (vulkan_ctx);
+}
+
 static void
 vulkan_set_2d (int scaled)
 {
@@ -612,6 +624,8 @@ vid_render_funcs_t vulkan_vid_render_funcs = {
 	.Draw_SubPic            = vulkan_Draw_SubPic,
 	.Draw_AddFont           = vulkan_Draw_AddFont,
 	.Draw_Glyph             = vulkan_Draw_Glyph,
+	.Draw_SetClip           = vulkan_Draw_SetClip,
+	.Draw_ResetClip         = vulkan_Draw_ResetClip,
 
 	.ParticleSystem   = vulkan_ParticleSystem,
 	.R_Init           = vulkan_R_Init,

libs/video/renderer/vulkan/vulkan_draw.c

@@ -87,6 +87,15 @@ typedef struct descbatch_s {
 typedef struct descbatchset_s
 	DARRAY_TYPE (descbatch_t) descbatchset_t;
 
+typedef struct drawclip_s {
+	uint32_t    start;
+	uint32_t    count;	// number of batches in quad_batch
+	VkRect2D    clip;
+} drawclip_t;
+
+typedef struct drawclipset_s
+	DARRAY_TYPE (drawclip_t) drawclipset_t;
+
 typedef struct {
 	float       xy[2];
 	byte        color[4];
@@ -167,6 +176,7 @@ typedef struct drawframe_s {
 	uint32_t    dvertex_index;
 	uint32_t    dvertex_max;
 	descbatchset_t quad_batch;
+	drawclipset_t clip_range;
 	quadqueue_t quad_insts;
 	linequeue_t line_verts;
 	descpool_t  dyn_descs;
@@ -428,6 +438,7 @@ create_buffers (vulkan_ctx_t *ctx)
 		};
 
 		DARRAY_INIT (&frame->quad_batch, 16);
+		DARRAY_INIT (&frame->clip_range, 16);
 		frame->quad_insts = (quadqueue_t) {
 			.quads = (quadinst_t *) ((byte *)data + frame->instance_offset),
 			.max_count = MAX_INSTANCES,
@@ -908,22 +919,32 @@ draw_quads (qfv_taskctx_t *taskctx)
 	dfunc->vkCmdBindIndexBuffer (cmd, ind_buffer, 0, VK_INDEX_TYPE_UINT32);
 
 	uint32_t    inst_start = 0;
-	for (size_t i = 0; i < dframe->quad_batch.size; i++) {
+	for (size_t i = 0; i < dframe->clip_range.size; i++) {
-		int         fontid = dframe->quad_batch.a[i].descid;
+		auto cr = &dframe->clip_range.a[i];
-		uint32_t    inst_count = dframe->quad_batch.a[i].count;
+		dfunc->vkCmdSetScissor (cmd, 0, 1, &cr->clip);
-		uint32_t    ind_count = inst_count >> 24;
+		for (uint32_t j = 0; j < cr->count; j++) {
-		inst_count &= 0xffffff;
+			int         fontid = dframe->quad_batch.a[cr->start + j].descid;
-		VkDescriptorSet set[2] = {
+			uint32_t    inst_count = dframe->quad_batch.a[cr->start + j].count;
-			Vulkan_Matrix_Descriptors (ctx, ctx->curFrame),
+			uint32_t    ind_count = inst_count >> 24;
-			fontid < 0 ? dframe->dyn_descs.sets[~fontid]
+			inst_count &= 0xffffff;
-					   : dctx->fonts.a[fontid].set,
+			VkDescriptorSet set[2] = {
-		};
+				Vulkan_Matrix_Descriptors (ctx, ctx->curFrame),
-		dfunc->vkCmdBindDescriptorSets (cmd, VK_PIPELINE_BIND_POINT_GRAPHICS,
+				fontid < 0 ? dframe->dyn_descs.sets[~fontid]
-										layout, 0, 2, set, 0, 0);
+						   : dctx->fonts.a[fontid].set,
+			};
+			dfunc->vkCmdBindDescriptorSets (cmd,
+											VK_PIPELINE_BIND_POINT_GRAPHICS,
+											layout, 0, 2, set, 0, 0);
 
-		dfunc->vkCmdDrawIndexed (cmd, ind_count, inst_count, 0, 0, inst_start);
+			dfunc->vkCmdDrawIndexed (cmd, ind_count, inst_count, 0, 0,
-		inst_start += inst_count;
+									 inst_start);
+			inst_start += inst_count;
+		}
 	}
+	VkRect2D scissor = {
+		.extent = { .width = vid.width, .height = vid.height },
+	};
+	dfunc->vkCmdSetScissor (cmd, 0, 1, &scissor);
 	DARRAY_RESIZE (&dframe->quad_batch, 0);
 }
 
@@ -973,6 +994,9 @@ slice_draw (const exprval_t **params, exprval_t *result, exprctx_t *ectx)
 		return;
 	}
 
+	auto cr = &dframe->clip_range.a[dframe->clip_range.size - 1];
+	cr->count = dframe->quad_batch.size - cr->start;
+
 	qftVkScopedZone (taskctx->frame->qftVkCtx, taskctx->cmd, "slice_draw");
 	VkDeviceMemory memory = dctx->draw_resource[1].memory;
 	size_t      atom = device->physDev->p.properties.limits.nonCoherentAtomSize;
@@ -1035,6 +1059,13 @@ draw_scr_funcs (const exprval_t **params, exprval_t *result, exprctx_t *ectx)
 	auto taskctx = (qfv_taskctx_t *) ectx;
 	auto ctx = taskctx->ctx;
 	auto dctx = ctx->draw_context;
+	auto dframe = &dctx->frames.a[ctx->curFrame];
+
+	DARRAY_RESIZE (&dframe->clip_range, 0);
+	DARRAY_APPEND (&dframe->clip_range, ((drawclip_t) {
+		.clip.offset = { .x = 0, .y = 0 },
+		.clip.extent = { .width = vid.width, .height = vid.height },
+	}));
 
 	auto scr_funcs = dctx->scr_funcs;
 	if (!scr_funcs) {
@@ -1047,9 +1078,8 @@ draw_scr_funcs (const exprval_t **params, exprval_t *result, exprctx_t *ectx)
 	dctx->scr_funcs = 0;
 
 	flush_vertqueue (&dctx->slice_vert_queue, ctx);
-	auto frame = &dctx->frames.a[ctx->curFrame];
+	flush_vertqueue (&dframe->dyn_vert_queue, ctx);
-	flush_vertqueue (&frame->dyn_vert_queue, ctx);
+	dframe->dyn_vert_queue.base = 0;
-	frame->dyn_vert_queue.base = 0;
 }
 
 static exprfunc_t flush_draw_func[] = {
@@ -1759,6 +1789,38 @@ Vulkan_Draw_Glyph (int x, int y, int fontid, int glyph, int c,
 	draw_quad (x, y, fontid, glyph * 4, color, frame);
 }
 
+void
+Vulkan_Draw_SetClip (int x, int y, int w, int h, vulkan_ctx_t *ctx)
+{
+	auto dctx = ctx->draw_context;
+	auto dframe = &dctx->frames.a[ctx->curFrame];
+
+	if (x < 0) {
+		w += x;
+		x = 0;
+	}
+	if (y < 0) {
+		h += y;
+		y = 0;
+	}
+	auto cr = &dframe->clip_range.a[dframe->clip_range.size - 1];
+	if (x != cr->clip.offset.x || y != cr->clip.offset.y
+		|| (uint32_t) w != cr->clip.extent.width
+		|| (uint32_t) h != cr->clip.extent.height) {
+		cr->count = dframe->quad_batch.size - cr->start;
+		DARRAY_APPEND (&dframe->clip_range, ((drawclip_t) {
+			.start = dframe->quad_batch.size,
+			.clip.offset = { .x = x, .y = y },
+			.clip.extent = { .width = w, .height = h },
+		}));
+	}
+}
+
+void
+Vulkan_Draw_ResetClip (vulkan_ctx_t *ctx)
+{
+}
+
 void
 Vulkan_LineGraph (int x, int y, int *h_vals, int count, int height,
 				  vulkan_ctx_t *ctx)