text rendering working

3 files changed, 38 insertions, 41 deletions

diff --git a/sim.cpp b/sim.cpp
index ffa3dd3..e56a7e3 100644
--- a/sim.cpp
+++ b/sim.cpp
@@ -345,7 +345,7 @@ void sim_frame(Frame *frame) {
 		state->platform_thickness = 0.005f;
 		state->bottom_y = 0.1f;
 
-		text_font_load(state, &state->font, "assets/font.ttf", 48.0f);
+		text_font_load(state, &state->font, "assets/font.ttf", 36.0f);
 
 		ball->radius = 0.02f;
 		ball->pos = V2(0.5f, 0.8f);
@@ -408,6 +408,7 @@ void sim_frame(Frame *frame) {
 #endif
 
 	b2World *world = state->world;
+	Font *font = &state->font;
 
 	// simulate physics
 	{
@@ -425,9 +426,10 @@ void sim_frame(Frame *frame) {
 
 			if (ball->pos.y - ball->radius < state->bottom_y) {
 				// oh no! ball reached bottom line
-				printf("Score: %f m\n", ball_pos.x);
 				world->DestroyBody(ball->body);
 				ball->body = NULL;
+			} else {
+				state->distance_traveled = ball_pos.x;
 			}
 		}
 		for (Platform *platform = state->platforms, *end = platform + state->nplatforms; platform != end; ++platform) {
@@ -456,9 +458,22 @@ void sim_frame(Frame *frame) {
 		glVertex2f(-1, line_pos.y);
 		glVertex2f(+1, line_pos.y);
 		glEnd();
+		glBegin(GL_QUADS);
+		glColor4f(1,0,0,0.1f);
+		glVertex2f(-1, line_pos.y);
+		glVertex2f(-1, -1);
+		glVertex2f(+1, -1);
+		glVertex2f(+1, line_pos.y);
+		glEnd();
 	}
 
-	text_render2f(state, &state->font, "Hello", 0, 0);
+	{
+		char text[256] = {0};
+		glColor3f(0.8f,0.5f,1);
+		snprintf(text, sizeof text - 1, "Distance: %.2f m", state->distance_traveled);
+		v2 size = text_get_size(state, font, text);
+		text_render(state, font, text, v2_sub(V2(0.95f, 0.95f), size));
+	}
 
 	#if DEBUG
 	GLuint error = glGetError();
diff --git a/sim.hpp b/sim.hpp
index 2b52c6d..4833d60 100644
--- a/sim.hpp
+++ b/sim.hpp
@@ -156,6 +156,8 @@ typedef struct {
 	Ball ball;
 	float bottom_y; // if y goes below here, it's over
 
+	float distance_traveled;
+
 	Font font;
 
 	float platform_thickness;
diff --git a/text.cpp b/text.cpp
index c3c3de4..1db0226 100644
--- a/text.cpp
+++ b/text.cpp
@@ -81,20 +81,18 @@ static bool text_font_load(State *state, Font *font, char const *filename, float
 	return success;
 }
 
-static void text_render_(State *state, Font *font, char const *s, float *xp, float *yp, bool render, float clip_left) {
+static void text_render_(State *state, Font *font, char const *s, float *xp, float *yp, bool render) {
 	if (!font->char_height) return; // font not loaded properly
 
 	stbtt_bakedchar *cdata = font->char_data;
 	int tex_w = font->tex_width, tex_h = font->tex_height;
 	float x = *xp, y = *yp;
-	// stb_truetype uses a pixel-based top-is-y=0 coordinate system, so we need to convert back and forth 
-	float resolution = (float)state->win_height;
-	float inv_resolution = 1 / resolution;
+	float widthf = (float)state->win_width, heightf = (float)state->win_height;
+	float inv_widthf = 1.0f / widthf, inv_heightf = 1.0f / heightf;
 
-	
-	x *= resolution;
-	y = 1 - y;
-	y *= resolution;
+	// convert between GL and stb_truetype coordinates
+	x = (x + 1) * 0.5f * widthf;
+	y = (1 - (y + 1) * 0.5f) * heightf;
 
 	glEnable(GL_TEXTURE_2D);
 	glBindTexture(GL_TEXTURE_2D, font->texture);
@@ -105,28 +103,10 @@ static void text_render_(State *state, Font *font, char const *s, float *xp, flo
 			stbtt_aligned_quad q = {};
 			stbtt_GetBakedQuad(cdata, tex_w, tex_h, c - 32, &x, &y, &q, 1);
 			if (render) {
-				q.x0 *= inv_resolution;
-				q.y0 *= inv_resolution;
-				q.x1 *= inv_resolution;
-				q.y1 *= inv_resolution;
-				q.y0 = 1 - q.y0;
-				q.y1 = 1 - q.y1;
-#if 1
-				if (q.x1 < clip_left) {
-					// entirety of character is to the left of clip_left. 
-				} else if (q.x0 < clip_left) {
-					// part of character is to the left of clip_left 
-					float char_width = q.x1 - q.x0; // full width of character 
-					float display_char_width = q.x1 - clip_left; // width of character which is being rendered, after clipping 
-					float char_fraction = display_char_width / char_width; // fraction of character rendered 
-					float s0 = q.s1 - char_fraction * (q.s1 - q.s0); // calculate where to start from 
-					float x0 = clip_left;
-					glTexCoord2f(  s0, q.t0); glVertex2f(  x0, q.y0);
-					glTexCoord2f(q.s1, q.t0); glVertex2f(q.x1, q.y0);
-					glTexCoord2f(q.s1, q.t1); glVertex2f(q.x1, q.y1);
-					glTexCoord2f(  s0, q.t1); glVertex2f(  x0, q.y1);
-				} else 
-#endif
+				q.x0 = (q.x0 * inv_widthf) * 2 - 1;
+				q.x1 = (q.x1 * inv_widthf) * 2 - 1;
+				q.y0 = (1 - q.y0 * inv_heightf) * 2 - 1;
+				q.y1 = (1 - q.y1 * inv_heightf) * 2 - 1;
 				{
 					// no clipping 
 					#if 0
@@ -142,25 +122,25 @@ static void text_render_(State *state, Font *font, char const *s, float *xp, flo
 	}
 	glEnd();
 	glDisable(GL_TEXTURE_2D);
-	*xp =     x * inv_resolution;
-	*yp = 1 - y * inv_resolution;
+	*xp = (x * inv_widthf) * 2 - 1;
+	*yp = (1 - y * inv_heightf) * 2 - 1;
 }
 
 static void text_render2f(State *state, Font *font, char const *s, float x, float y) {
-	text_render_(state, font, s, &x, &y, true, 0);
+	text_render_(state, font, s, &x, &y, true);
 }
 static void text_render(State *state, Font *font, char const *s, v2 pos) {
-	text_render_(state, font, s, &pos.x, &pos.y, true, 0);
+	text_render_(state, font, s, &pos.x, &pos.y, true);
 }
 
-static float text_font_char_height(Font *font) {
-	return font->char_height * 0.666667f;
+static float text_font_char_height(State *state, Font *font) {
+	return font->char_height / (float)state->win_width * 1.3333333f;
 }
 
 static v2 text_get_size(State *state, Font *font, char const *s) {
 	float x = 0, y = 0;
-	text_render_(state, font, s, &x, &y, false, 0);
-	return V2(x, y + text_font_char_height(font));
+	text_render_(state, font, s, &x, &y, false);
+	return V2(x, y + text_font_char_height(state, font));
 }
 
 static void text_render_centered(State *state, Font *font, char const *s, v2 center) {