From eadf3524ba1a51eb53d87d9ab26962204cc8ed05 Mon Sep 17 00:00:00 2001
From: John Alanbrook <john@pockle.world>
Date: Fri, 30 Dec 2022 19:31:06 +0000
Subject: [PATCH] UV and ST

---
 source/engine/editor/editor.c | 10 ++++-----
 source/engine/font.h          | 10 ++-------
 source/engine/sprite.c        | 30 ++++++++++++++-----------
 source/engine/sprite.h        |  1 -
 source/engine/texture.c       | 42 +++++++++++++----------------------
 source/engine/texture.h       | 30 ++++++++++++++++++-------
 6 files changed, 62 insertions(+), 61 deletions(-)

diff --git a/source/engine/editor/editor.c b/source/engine/editor/editor.c
index 522782c..60261b8 100644
--- a/source/engine/editor/editor.c
+++ b/source/engine/editor/editor.c
@@ -869,12 +869,12 @@ void editor_asset_tex_gui(struct Texture *tex) {
         if (old_frames != tex->anim.frames || old_ms != tex->anim.ms)
             tex_anim_set(&tex_gui_anim);
 
-        nk_layout_row_static(ctx, tex->height*tex_scale*tex_gui_anim.uv.h, tex->width*tex_scale*tex_gui_anim.uv.w, 1);
+        nk_layout_row_static(ctx, tex->height*tex_scale*(tex_gui_anim.st.t1-tex_gui_anim.st.t0), tex->width*tex_scale*(tex_gui_anim.st.s1 - tex_gui_anim.st.s0), 1);
         struct nk_rect r;
-        r.x = tex_gui_anim.uv.x*tex->width;
-        r.y = tex_gui_anim.uv.y*tex->height;
-        r.w = tex_gui_anim.uv.w*tex->width;
-        r.h = tex_gui_anim.uv.h*tex->height;
+        r.x = tex_gui_anim.st.s0*tex->width;
+        r.y = tex_gui_anim.st.t0*tex->height;
+        r.w = st_s_w(tex_gui_anim.st)*tex->width;
+        r.h = st_s_h(tex_gui_anim.st)*tex->height;
 
         nk_image(ctx, nk_subimage_id(tex->id, tex->width, tex->height, r));
     } else {
diff --git a/source/engine/font.h b/source/engine/font.h
index e7d9dd0..cdf13b4 100644
--- a/source/engine/font.h
+++ b/source/engine/font.h
@@ -2,17 +2,11 @@
 #define FONT_H
 
 #include "mathc.h"
+#include "texture.h"
 
 struct shader;
 struct window;
 
-struct glrect {
-    float s0;
-    float s1;
-    float t0;
-    float t1;
-};
-
 /// Holds all state information relevant to a character as loaded using FreeType
 struct Character {
     mfloat_t Size[2];		// Size of glyph
@@ -28,7 +22,7 @@ struct sFont {
     uint32_t texID;
 };
 
-struct glrect runit = { 0.f, 1.f, 0.f, 1.f };
+
 
 void font_init(struct shader *s);
 void font_frame(struct window *w);
diff --git a/source/engine/sprite.c b/source/engine/sprite.c
index 1191124..330445f 100644
--- a/source/engine/sprite.c
+++ b/source/engine/sprite.c
@@ -1,6 +1,5 @@
 #include "sprite.h"
 
-
 #include "timer.h"
 #include "render.h"
 #include "openglrender.h"
@@ -87,16 +86,6 @@ void sprite_loadtex(struct sprite *sprite, const char *path)
     sprite->tex = texture_loadfromfile(path);
 }
 
-void sprite_loadanim(struct sprite *sprite, const char *path, struct Anim2D anim)
-{
-    sprite->tex = texture_loadfromfile(path);
-    sprite->anim = anim;
-    sprite->anim.timer = timer_make(sprite->anim.ms, &incrementAnimFrame, sprite);
-/*
-    sprite->tex = texture_loadanimfromfile(sprite->tex, path, sprite->anim.frames, sprite->anim.dimensions);
-*/
-}
-
 void sprite_settex(struct sprite *sprite, struct Texture *tex)
 {
     sprite->tex = tex;
@@ -122,7 +111,13 @@ void sprite_initialize()
     glEnableVertexAttribArray(0);
 }
 
+struct glrect sprite_get_rect(struct sprite *sprite) {
+    if (sprite->tex->opts.animation) {
 
+    } else {
+        return tex_get_rect(sprite->tex);
+    }
+}
 
 void tex_draw(struct Texture *tex, float pos[2], float angle, float size[2], float offset[2], struct glrect r) {
 	mfloat_t model[16] = { 0.f };
@@ -173,9 +168,18 @@ void sprite_draw(struct sprite *sprite)
         cpVect cpos = cpBodyGetPosition(sprite->go->body);
         float pos[2] = {cpos.x, cpos.y};
 
-        float size[2] = { sprite->size[0] * sprite->go->scale, sprite->size[1] * sprite->go->scale };
+        if (sprite->tex->opts.animation) {
+            float size[2];
+            struct Anim2D *a = &sprite->anim;
+            a->frames = sprite->tex->anim.frames;
+            size[0] = sprite->tex->anim.dimensions[0];
+            size[1] = sprite->tex->anim.dimensions[1];
+            tex_draw(sprite->tex, pos, cpBodyGetAngle(sprite->go->body), size, sprite->pos, tex_get_rect(sprite->tex));
+        } else {
+            float size[2] = { sprite->size[0] * sprite->go->scale, sprite->size[1] * sprite->go->scale };
 
-        tex_draw(sprite->tex, pos, cpBodyGetAngle(sprite->go->body), size, sprite->pos, tex_get_rect(sprite->tex));
+            tex_draw(sprite->tex, pos, cpBodyGetAngle(sprite->go->body), size, sprite->pos, tex_get_rect(sprite->tex));
+        }
     }
 }
 
diff --git a/source/engine/sprite.h b/source/engine/sprite.h
index a25320c..0a597fc 100644
--- a/source/engine/sprite.h
+++ b/source/engine/sprite.h
@@ -36,7 +36,6 @@ void sprite_delete(struct sprite *sprite);
 void sprite_init(struct sprite *sprite, struct gameobject *go);
 void sprite_io(struct sprite *sprite, FILE *f, int read);
 void sprite_loadtex(struct sprite *sprite, const char *path);
-void sprite_loadanim(struct sprite *sprite, const char *path, struct Anim2D anim);
 void sprite_settex(struct sprite *sprite, struct Texture *tex);
 void sprite_initialize();
 void sprite_draw(struct sprite *sprite);
diff --git a/source/engine/texture.c b/source/engine/texture.c
index 98cd53d..15ed840 100644
--- a/source/engine/texture.c
+++ b/source/engine/texture.c
@@ -80,8 +80,6 @@ struct Texture *texture_loadfromfile(const char *path)
     return new;
 }
 
-
-
 void tex_pull(struct Texture *tex)
 {
     if (tex->data != NULL)
@@ -184,35 +182,19 @@ void tex_gpu_free(struct Texture *tex)
 
 void tex_anim_calc_uv(struct TexAnimation *anim)
 {
-    struct Rect uv;
-    uv.w = 1.f / anim->tex->anim.frames;
-    uv.h = 1.f;
-    uv.y = 0.f;
-    uv.x = uv.w * (anim->frame);
+    struct glrect st;
+    float w = 1.f / anim->tex->anim.frames;
+    st.s0 = w * (anim->frame);
+    st.s1 = st.s0 + w;
+    st.t0 = 0.f;
+    st.t1 = 1.f;
 
-    anim->uv = uv;
+    anim->st = st;
 }
 
-
-
 struct glrect tex_get_rect(struct Texture *tex)
 {
-    if (tex->opts.animation) {
-    /*
-        tex_anim_calc_uv(tex->anim);
-        struct glrect ret;
-
-        ret.s0 = tex->anim.uv.x;
-        ret.s1 = tex->anim.uv.x + tex->anim.uv.w;
-        ret.t0 = tex->anim.uv.y;
-        ret.t1 = tex->anim.uv.y + tex->anim.uv.h;
-*/
-        return runit;
-    } else {
-        return runit;
-    }
-
-    return runit;
+    return ST_UNIT;
 }
 
 void tex_bind(struct Texture *tex)
@@ -271,4 +253,12 @@ void anim_bkwd(struct TexAnimation *anim)
     anim_decr(anim);
 }
 
+float st_s_w(struct glrect st)
+{
+    return (st.s1 - st.s0);
+}
 
+float st_s_h(struct glrect st)
+{
+    return (st.t1 - st.t0);
+}
\ No newline at end of file
diff --git a/source/engine/texture.h b/source/engine/texture.h
index 8a441db..b57f73f 100644
--- a/source/engine/texture.h
+++ b/source/engine/texture.h
@@ -2,30 +2,44 @@
 #define TEXTURE_H
 
 #include "timer.h"
-#include "font.h"
 
 #define TEX_SPEC 0
 #define TEX_NORM 1
 #define TEX_HEIGHT 2
 #define TEX_DIFF 3
 
-
-struct Rect {
-    float x;
-    float y;
-    float w;
-    float h;
+/* Normalized S,T coordinates for rendering */
+struct glrect {
+    float s0;
+    float s1;
+    float t0;
+    float t1;
 };
 
+float st_s_w(struct glrect st);
+float st_s_h(struct glrect st);
+
+#define ST_UNIT (struct glrect) { 0.f, 1.f, 0.f, 1.f }
+
+/* Pixel U,V coordiantes */
+struct uvrect {
+    int u0;
+    int u1;
+    int v0;
+    int v1;
+};
+
+/* Tracks a playing animation */
 struct TexAnimation {
     int frame;
     int playing;
     int pausetime;
     struct timer *timer;
-    struct Rect uv;
+    struct glrect st; /* Current ST coordinates for active frame */
     struct Texture *tex;
 };
 
+/* Describes an animation on a particular texture */
 struct TexAnim {
     int frames;
     int dimensions[2];