added dynamic sw_vertex_buffer and changed gsa to use it

include/vertex_buffer.h

@@ -0,0 +1,20 @@
+#ifndef GUARD_B3E8DB670A75ACCB1082192FB0485037
+#define GUARD_B3E8DB670A75ACCB1082192FB0485037
+
+#include "types.h"
+
+struct sw_vertex_buffer {
+	u32 elem_size;
+	u32 elem_count;
+	u32 elem_capacity;
+	void *data;
+};
+
+struct sw_vertex_buffer *sw_vertex_buffer_create(u32 elem_size);
+void sw_vertex_buffer_destroy(struct sw_vertex_buffer *vb);
+
+/* copies elem data */
+void sw_vertex_buffer_add(struct sw_vertex_buffer *vb, void *elem);
+void sw_vertex_buffer_clear(struct sw_vertex_buffer *vb);
+
+#endif /* GUARD_B3E8DB670A75ACCB1082192FB0485037 */

src/gsa.c

@@ -6,6 +6,7 @@
 #include "shader.h"
 #include "skip.h"
 #include "types.h"
+#include "vertex_buffer.h"
 #include "window.h"
 #include <gl/gl.h>
 #include <string.h>
@@ -39,6 +40,8 @@ static u32 tex;
 static bool (*loop_stack[GSA_LOOP_STACK_SIZE])();
 static i8 loop_stack_i;
 
+static struct sw_vertex_buffer *vertex_buffer;
+
 int gsa_main(int argc, char *argv[]) {
 	(void)argc;
 	(void)argv;
@@ -53,6 +56,8 @@ int gsa_main(int argc, char *argv[]) {
 	data = sw_skip_get(sw_skip_self, "gfx.png", &size);
 	_gfx = sw_image8_load_png_data(data, size);
 
+	vertex_buffer = sw_vertex_buffer_create(sizeof(struct render_vert));
+
 	memset(loop_stack, 0, sizeof(loop_stack));
 	loop_stack_i = -1;
 
@@ -137,11 +142,12 @@ void gsa_run_loop(bool (*loopfun)()) {
 }
 
 static void add_render_vert(f32 x, f32 y, f32 tx, f32 ty) {
-	render_verts[next_render_vert].x = x;
-	render_verts[next_render_vert].y = y;
-	render_verts[next_render_vert].tx = tx;
-	render_verts[next_render_vert].ty = ty;
-	++next_render_vert;
+	struct render_vert v;
+	v.x = x;
+	v.y = y;
+	v.tx = tx;
+	v.ty = ty;
+	sw_vertex_buffer_add(vertex_buffer, &v);
 }
 
 static void rect(f32 x, f32 y, f32 w, f32 h, i16 tile, bool half) {
@@ -191,7 +197,7 @@ void _gsa_tick() {
 		}
 	}
 
-	next_render_vert = 0;
+	sw_vertex_buffer_clear(vertex_buffer);
 
 	for(i = 0; i < MAX_TILEMAPS; ++i) {
 		tcmult = maps[i].half_tile ? 2 : 1;
@@ -243,11 +249,11 @@ void _gsa_tick() {
 	);
 	glBufferData(
 	    GL_ARRAY_BUFFER,
-	    sizeof(struct render_vert) * (next_render_vert),
-	    render_verts,
+	    sizeof(struct render_vert) * vertex_buffer->elem_count,
+	    vertex_buffer->data,
 	    GL_DYNAMIC_DRAW
 	);
-	glDrawArrays(GL_TRIANGLES, 0, next_render_vert);
+	glDrawArrays(GL_TRIANGLES, 0, vertex_buffer->elem_count);
 	glBindVertexArray(0);
 	/* glEnd(); */
 }

src/skunkworks.h

@@ -1,13 +0,0 @@
-/***************************************************************************/
-/*   ___________                 __                         __             */
-/*  /   _____/  | ____ __  ____ |  | ____  _  _____________|  | __  ______ */
-/*  \_____  \|  |/ /  |  \/    \|  |/ /\ \/ \/ /  _ \_  __ \  |/ / /  ___/ */
-/*  /        \    <|  |  /   |  \    <  \     (  <_> )  | \/    <  \___ \  */
-/* /_______  /__|_ \____/|___|  /__|_ \  \/\_/ \____/|__|  |__|_ \/____  > */
-/*         \/     \/          \/     \/                         \/     \/  */
-/***************************************************************************/
-
-#ifndef GUARD_BAEE408B8F416CA55711305ABAF9CE6C
-#define GUARD_BAEE408B8F416CA55711305ABAF9CE6C
-
-#endif /* GUARD_BAEE408B8F416CA55711305ABAF9CE6C */

src/vertex_buffer.c

@@ -0,0 +1,43 @@
+#include "vertex_buffer.h"
+
+#include "skunkworks.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+struct sw_vertex_buffer *sw_vertex_buffer_create(u32 elem_size) {
+	struct sw_vertex_buffer *vb;
+
+	vb = malloc(sizeof(struct sw_vertex_buffer));
+	/* initial capacity... 8? dunno :P */
+	vb->elem_capacity = 8;
+	vb->data = malloc(elem_size * vb->elem_capacity);
+	vb->elem_count = 0;
+	vb->elem_size = elem_size;
+
+	return vb;
+}
+
+void sw_vertex_buffer_destroy(struct sw_vertex_buffer *vb) {
+	free(vb->data);
+	free(vb);
+}
+
+void sw_vertex_buffer_add(struct sw_vertex_buffer *vb, void *elem) {
+	if(vb->elem_count == vb->elem_capacity) {
+		/* grow capacity... double for now? */
+		vb->elem_capacity *= 2;
+		sw_log("increase vertex buffer size to %i", vb->elem_capacity);
+		vb->data = realloc(vb->data, vb->elem_size * vb->elem_capacity);
+	}
+	memcpy(
+	    (u8 *)vb->data + vb->elem_count * vb->elem_size, elem, vb->elem_size
+	);
+
+	++vb->elem_count;
+}
+
+void sw_vertex_buffer_clear(struct sw_vertex_buffer *vb) {
+	/* keep capacity */
+	vb->elem_count = 0;
+}