ogc: simplify viewport setup

We can just use an identity matrix for the model view matrix. The only
transformation we apply is the 0.5 shift to get the coordinates centered
on the pixels.

Author: mardy

src/render/ogc/SDL_render_ogc.c

@@ -333,10 +333,7 @@ static int OGC_RenderSetViewPort(SDL_Renderer *renderer, SDL_RenderCommand *cmd)
 {
     const SDL_Rect *viewport = &cmd->data.viewport.rect;
 
-    float v_aspect = viewport->h / 2.0;
-    float h_aspect = viewport->w / 2.0;
-    OGC_set_viewport(viewport->x, viewport->y, viewport->w, viewport->h,
-                     h_aspect, v_aspect);
+    OGC_set_viewport(viewport->x, viewport->y, viewport->w, viewport->h);
     return 0;
 }
 

src/video/ogc/SDL_ogcgxcommon.c

@@ -29,18 +29,6 @@
 #include <ogc/gx.h>
 #include <ogc/video.h>
 
-typedef struct tagcamera {
-    guVector pos;
-    guVector up;
-    guVector view;
-} camera;
-
-static camera cam = {
-    { 0.0F, 0.0F, 0.0F },
-    { 0.0F, -0.5F, 0.0F },
-    { 0.0F, 0.0F, 0.5F }
-};
-
 static const f32 tex_pos[] __attribute__((aligned(32))) = {
     0.0,
     0.0,
@@ -52,30 +40,28 @@ static const f32 tex_pos[] __attribute__((aligned(32))) = {
     1.0,
 };
 
-void OGC_set_viewport(int x, int y, int w, int h, float h_aspect, float v_aspect)
+void OGC_set_viewport(int x, int y, int w, int h)
 {
-    Mtx m, mv, view;
     Mtx44 proj;
 
     GX_SetViewport(x, y, w, h, 0, 1);
     GX_SetScissor(x, y, w, h);
 
-    memset(&view, 0, sizeof(Mtx));
-    guLookAt(view, &cam.pos, &cam.up, &cam.view);
-    guMtxIdentity(m);
-    guMtxTransApply(m, m, 0.5 + (-w / 2.0), 0.5 + (-h / 2.0), 1000);
-    guMtxConcat(view, m, mv);
-    GX_LoadPosMtxImm(mv, GX_PNMTX0);
-
     // matrix, t, b, l, r, n, f
-    guOrtho(proj, v_aspect, -v_aspect, -h_aspect, h_aspect, 100, 1000);
+    guOrtho(proj, 0, h, 0, w, 0, 1);
     GX_LoadProjectionMtx(proj, GX_ORTHOGRAPHIC);
 }
 
-void OGC_draw_init(int w, int h, int h_aspect, int v_aspect)
+void OGC_draw_init(int w, int h)
 {
+    Mtx mv;
+
     SDL_LogDebug(SDL_LOG_CATEGORY_VIDEO, "OGC_draw_init called with %d, %d", w, h);
 
+    guMtxIdentity(mv);
+    guMtxTransApply(mv, mv, 0.5, 0.5, 0);
+    GX_LoadPosMtxImm(mv, GX_PNMTX0);
+
     GX_ClearVtxDesc();
     GX_SetVtxDesc(GX_VA_POS, GX_DIRECT);
     GX_SetVtxDesc(GX_VA_TEX0, GX_INDEX8);
@@ -94,7 +80,7 @@ void OGC_draw_init(int w, int h, int h_aspect, int v_aspect)
     GX_SetTevOp(GX_TEVSTAGE0, GX_REPLACE);
     GX_SetTevOrder(GX_TEVSTAGE0, GX_TEXCOORD0, GX_TEXMAP0, GX_COLOR0A0);
 
-    OGC_set_viewport(0, 0, w, h, h_aspect, v_aspect);
+    OGC_set_viewport(0, 0, w, h);
 
     GX_InvVtxCache(); // update vertex cache
 }

src/video/ogc/SDL_ogcgxcommon.h

@@ -29,8 +29,8 @@
 
 #define GX_COLOR_AS_U32(c) *((u32*)&c)
 
-void OGC_draw_init(int w, int h, int h_aspect, int v_aspect);
-void OGC_set_viewport(int x, int y, int w, int h, float h_aspect, float v_aspect);
+void OGC_draw_init(int w, int h);
+void OGC_set_viewport(int x, int y, int w, int h);
 void OGC_load_texture(void *texels, int w, int h, u8 gx_format,
                       SDL_ScaleMode scale_mode);
 

src/video/ogc/SDL_ogcvideo.c

@@ -107,7 +107,6 @@ int OGC_VideoInit(_THIS)
     SDL_DisplayMode mode;
     GXRModeObj *vmode;
     static const GXColor background = { 0, 0, 0, 255 };
-    int h_aspect, v_aspect;
 
     VIDEO_Init();
 
@@ -142,10 +141,7 @@ int OGC_VideoInit(_THIS)
 
     GX_SetZMode(GX_TRUE, GX_LEQUAL, GX_TRUE);
 
-    /* Should we need to adjust the aspect, this is the place to do it */
-    h_aspect = 320;
-    v_aspect = 240;
-    OGC_draw_init(vmode->fbWidth, vmode->efbHeight, h_aspect, v_aspect);
+    OGC_draw_init(vmode->fbWidth, vmode->efbHeight);
 
     GX_Flush();